Apparatus and method for determining effects of a substance of an organ

ABSTRACT

An organ perfusion apparatus and method monitor, sustain and/or restore viability of organs and preserve organs for storage and/or transport. Other apparatus include an organ transporter, an organ cassette and an organ diagnostic device. The method includes perfusing the organ at hypothermic and/or normothermic temperatures, preferably after hypothermic organ flushing for organ transport and/or storage. The method can be practiced with prior or subsequent static or perfusion hypothermic exposure of the organ. Organ viability is restored by restoring high energy nucleotide (e.g., ATP) levels by perfusing the organ with a medical fluid, such as an oxygenated cross-linked hemoglobin-based bicarbonate medical fluid, at normothermic temperatures. During the period in which the organ is preserved and/or maintained, various drug research and development may be performed on and/or with the organ. The organ may be perfused with a fluid containing a substance such as a test substance to obtain data regarding the organ, the substance and an interaction of the substance and the organ. The data may then be used to ultimately provide information regarding the drugs efficacy in support of regulatory filings for new drugs.

[0001] This application is a continuation-in-part of U.S. patentapplication Ser. No. 10/617,130 filed Jul. 11, 2003 which is aDivisional of application Ser. No. 09/645, 525 filed Aug. 25, 2000,which is a continuation-in-part of U.S. patent application Ser. No.09/537,180, filed Mar. 29, 2000, which is a continuation-in-part of U.S.patent application Ser. No. 09/162,128, filed Sep. 29, 1998, the entirecontents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of Invention

[0003] The invention relates to an apparatus and method for perfusingone or more organs to monitor, sustain and/or restore the viability ofthe organ(s) and/or for transporting and/or storing the organ(s). Thisinvention further relates to determining if the organ(s) is/are a viablecandidate for transplantation. Particularly, if the organ(s) is/are notviable transplantation candidates, then this invention further relatesto perfusing the organ(s) with a fluid to acquire data regarding theorgan(s) and/or fluid.

[0004] 2. Description of Related Art

[0005] Preservation of organs by machine perfusion has been accomplishedat hypothermic temperatures with or without computer control withcrystalloid perfusates and without oxygenation. See, for example, U.S.Pat. Nos. 5,149,321, 5,395,314, 5,584,804, 5,709,654 and 5,752,929 andU.S. patent application Ser. No. 08/484,601 to Klatz et al., which arehereby incorporated by reference. Hypothermic temperatures provide adecrease in organ metabolism, lower the energy requirements, delay thedepletion of high energy phosphate reserves and accumulation of lacticacid and retard the morphological and functional deteriorationassociated with disruption of blood supply. Oxygen can not be utilizedefficiently by mitochondria below approximately 20° C. to produceenergy, and the reduction in catalase/superoxide dismutase productionand ascorbyl and glutathione regeneration at low temperatures allowshigh free radical formation. The removal of oxygen from perfusatesduring low temperature machine perfusion has even proven helpful inimproving organ transplant results by some investigators.

[0006] Reduction in potential oxygen damage is also accomplished via theaddition of antioxidants to the perfusate. In particular, this hasproven useful in reducing organ damage after long warm ischemia times.Numerous other perfusate additives have also been reported to improvethe outcome of machine perfusion.

[0007] Ideally organs would be procured in a manner that limits theirwarm ischemia time to essentially zero. Unfortunately, in reality, manyorgans, especially from non-beating heart donors, are procured afterextended warm ischemia time periods (i.e., 45 minutes or more). Themachine perfusion of these organs at low temperature has demonstratedsignificant improvement (Transpl Int 1996 Daemen). Further, prior artteaches that the low temperature machine perfusion of organs ispreferred at low pressures (Transpl. Int 1996 Yland) with roller ordiaphragm pumps delivering the perfusate at a controlled pressure.Numerous control circuits and pumping configurations have been utilizedto achieve this objective and to machine perfuse organs in general. See,for example, U.S. Pat. Nos. 5,338,662 and 5,494,822 to Sadri; U.S. Pat.No. 4,745,759 to Bauer et al.; U.S. Pat. Nos. 5,217,860 and 5,472,876 toFahy et al.; U.S. Pat. No. 5,051,352 to Martindale et al.; U.S. Pat. No.3,995,444 to Clark et al.; U.S. Pat. No. 4,629,686 to Gruenberg; U.S.Pat. Nos. 3,738,914 and 3,892,628 to Thorne et al.; U.S. Pat. Nos.5,285,657 and 5,476,763 to Bacchi et al.; U.S. Pat. No. 5,157,930 toMcGhee et al.; and U.S. Pat. No. 5,141,847 to Sugimachi et al. However,in some situations the use of such pumps for machine perfusion of organsmay increase the risk of overpressurization of the organ should theorgan perfusion apparatus malfunction. High pressure perfusion (e.g.,above about 60 mm Hg) can wash off the vascular endothelial lining ofthe organ and in general damages organ tissue, in particular athypothermic temperatures where the organ does not have the neurologicalor endocrinal connections to protect itself by dilating its vasculatureunder high pressure.

[0008] Furthermore, the techniques used for assessment of the viabilityof these machine perfused organs have been a critical factor in limitingthe organs from greater use. While increased organ resistance (i.e.,pressure/flow) measurements during machine perfusion are a usefulindicator, they demonstrate only the worst case situations.

[0009] During low temperature machine perfusion of organs that have beendamaged by warm ischemia time or by the machine perfusion itself, theorgans will elute intracellular and endothelial as well as membraneconstituents. Over the years the appearance of various ubiquitousintracellular enzymes, such as lactic dehydrogenase (LDH) and alkalinephosphatase, in the perfusate has been used as a biomarker of organdamage. Recently, the determination of the presence of alphaglutathione-S-transferase (a-GST) and Pi glutathione-S-transferase(p-GST) in low temperature machine perfusion perfusates has proven asatisfactory indicator in predicting the functional outcome ofnon-beating heart donor kidney grafts before transplantation (Transpl1997 Daemen).

[0010] The prior art has also addressed the need to restore or maintainan organ's physiological function after preservation for an extendedperiod of time at hypothermic temperatures. In particular, U.S. Pat. No.5,066,578 to Wikman-Coffelt discloses an organ preservation solutionthat contains large amounts of pyruvate. Wikman-Coffelt teaches thatflooding of the organ with pyruvate bypasses glycosis, the step in thecell energy cycle that utilizes adenosine triphosphate (ATP) to producepyruvate, and pyruvate is then available to the mitochondria foroxidative phosphorylation producing ATP. Wikman-Coffelt teachesperfusing or washing an organ at a warm temperature with a firstpreservation solution containing pyruvate for removal of blood or otherdebris from the organ's vessels and to vasodilate, increase flow andload the cells with an energy supply in the form of a clean substrate,namely the pyruvate. Wikman-Coffelt teaches that the pyruvate preventsedema, ischemia, calcium overload and acidosis as well as helps preservethe action potential across the cell membrane. The organ is thenperfused with a second perfusion solution containing pyruvate and asmall percentage of ethanol in order to stop the organ from working,vasodilate the blood vessels allowing for full vascular flow, continueto load the cells with pyruvate and preserve the energy state of theorgan. Finally the organ is stored in a large volume of the firstsolution for 24 hours or longer at temperatures between 4° C. and 10° C.

[0011] However, the mitochondria are the source of energy in cells andneed significant amounts of oxygen to function. Organs naturally havesignificant pyruvate levels, and providing an organ with additionalpyruvate will not assist in restoring and/or maintaining an organ's fullphysiological function if the mitochondria are not provided withsufficient oxygen to function. Further, briefly flooding an organ withpyruvate may, in fact, facilitate tearing off of the vascularendothelial lining of the organ.

[0012] U.S. Pat. No. 5,599,659 to Brasile et al. also discloses apreservation solution for warm preservation of tissues, explants, organsand endothelial cells. Brasile et al. teaches disadvantages of coldorgan storage, and proposes warm preservation technology as analternative. Brasile et al. teaches that the solution has an enhancedability to serve as a medium for the culture of vascular endothelium oftissue, and as a solution for organs for transplantation using a warmpreservation technology because it is supplemented with serum albumin asa source of protein and colloid; trace elements to potentiate viabilityand cellular function; pyruvate and adenosine for oxidativephosphorylation support; transferrin as an attachment factor; insulinand sugars for metabolic support and glutathione to scavenge toxic freeradicals as well as a source of impermeant; cyclodextrin as a source ofimpermeant, scavenger, and potentiator of cell attachment and growthfactors; a high Mg++ concentration for microvessel metabolism support;mucopolysaccharides, comprising primarily chondroitin sulfates andheparin sulfates, for growth factor potentiation and hemostasis; andENDO GRO™ as a source of cooloid, impermeant and specific vasculargrowth promoters. Brasile et al. further teaches warm perfusing an organfor up to 12 hours at 30° C., or merely storing the organ attemperatures of 25° C. in the preservation solution.

[0013] However, flooding an organ with such chemicals is insufficient toarrest or repair ischemic injury where the mitochondria are not providedwith sufficient oxygen to function to produce energy. The oxygen needsof an organ at more than 20° C. are substantial and cannot be met by asimple crystalloid at reasonable flows. Further, assessment of theviability of an organ is necessary before the use of any type ofsolution can be determined to have been fruitful.

[0014] WO 88/05261 to Owen discloses an organ perfusion system includingan organ chamber that is supplied with an emulsion fluid orphysiological electrolyte that is transported through a perfusionsystem. The chamber contains a synthetic sac to hold the organ.Perfusate enters the organ through a catheter inserted into an artery.The perfusate is provided by two independent fluid sources, each ofwhich includes two reservoirs.

SUMMARY OF THE INVENTION

[0015] The present invention focuses on avoiding damage to an organduring perfusion while monitoring, sustaining and/or restoring theviability of the organ and preserving the organ for storage, transport,transplantation or other use. The invention is directed to an apparatusand method for perfusing an organ to monitor, sustain and/or restore theviability of the organ and/or for transporting and/or storing and/orusing the organ. More particularly, the organ perfusion apparatus andmethod according to the invention monitor, sustain and/or restore organviability by perfusing the organ at hypothermic temperature (hypothermicperfusion mode) and/or normothermic temperatures (normothermic perfusionmode) preferably after flushing of the organ such as by hypothermicflushing followed by static organ storage and/or organ perfusion athypothermic temperatures for transport and/or storage of the organ.

[0016] The restoring of organ viability may be accomplished by restoringhigh energy nucleotide (e.g., adenosine triphosphate (ATP)) levels andenzyme levels in the organ, which were reduced by warm ischemia timeand/or hypoxia, by perfusing the organ with an oxygenated medical fluid,such as an oxygenated cross-linked hemoglobin-based bicarbonate medicalfluid, at normothermic or near-normothermic temperatures. The organ maybe flushed with a medical fluid prior to perfusion with the oxygenatedmedical fluid. Such perfusion can be performed at either normothermic orhypothermic temperatures, preferably at hypothermic temperatures. Forhypothermic flush, static storage and hypothermic perfusion, the medicalfluid preferably contains little or no oxygen and preferably includesantioxidants, both molecular (e.g., 2-ascorbic acid tocopherol) andenzymatic (e.g., catalase and superoxide dismutase (SOD)). Normothermicand/or hypothermic perfusion, and preferably hypothermic perfusion, canbe performed in vivo as well as in vitro. Such perfusion arrestsischemic injury in preparation for transport, storage and/or transplantof the organ.

[0017] The normothermic treatment is preferably employed after an organhas been subjected to hypothermic temperatures, statically and/or underperfusion. Such initial hypothermic exposure can occur, for example,during transport and/or storage of an organ after harvesting. Thetreatment is also suitable for organs that will ultimately be storedand/or transported under hypothermic conditions. In other words, thetreatment can be applied to organs prior to cold storage and/ortransport.

[0018] In the normothermic perfusion mode, gross organ perfusionpressure is preferably provided by a pneumatically pressurized medicalfluid reservoir controlled in response to a sensor disposed in an end oftubing placed in the organ, which may be used in combination with astepping motor/cam valve or pinch valve which provides for perfusionpressure fine tuning, prevents overpressurization and/or providesemergency flow cut-off. Alternatively, the organ may be perfuseddirectly from a pump, such as a roller pump or a peristaltic pump, withproper pump control and/or sufficiently fail-safe controllers to preventoverpressurization of the organ, especially as a result of a systemmalfunction. Substantially eliminating overpressurization preventsand/or reduces damage to the vascular endothelial lining and to theorgan tissue in general. Viability of the organ may be monitored,preferably automatically, in the normothermic perfusion mode, preferablyby monitoring organ resistance (pressure/flow) and/or pH, pO₂, pCO₂,LDH, T/GST, Tprotein, lactate, glucose, base excess and/or ionizedcalcium levels in the medical fluid that has been perfused through theorgan and collected.

[0019] Normothermic perfusion may be preceded by and/or followed byhypothermic perfusion. In the hypothermic mode, the organ is perfusedwith a medical fluid containing substantially no oxygen, preferably asimple crystalloid solution that may preferably be augmented withantioxidants, intermittently or at a slow continuous flow rate.Hypothermic perfusion also can be performed in vivo as well as in vitroprior to removal of the organ from the donor. Hypothermic perfusionreduces the organ's metabolic rate, allowing the organ to be preservedfor extended periods of time. The medical fluid is preferably fed intothe organ by pressure from an intermediary tank which has a low pressurehead so overpressurization of the organ is avoided. Alternatively, inembodiments, gravity can be used to feed the medical fluid into theorgan from the intermediary tank, if appropriate. Alternatively, theorgan may be perfused directly from a pump, such as a roller pump or aperistaltic pump, with proper pump control and/or sufficiently fail-safecontrollers to prevent overpressurization of the organ, especially as aresult of a system malfunction. Substantially eliminatingoverpressurization prevents or reduces damage to the vascularendothelial lining of the organ and to the organ tissue in general, inparticular at hypothermic temperatures when the organ has less abilityto protect itself by vascular constriction. Viability of the organ mayalso be monitored, preferably automatically, during the recoveryprocess, preferably by monitoring organ resistance (pressure/flow)and/or pH, pO₂, pCO₂, LDH, T/GST, Tprotein, lactate, glucose, baseexcess and/or ionized calcium levels in the medical fluid that has beenperfused through the organ and collected.

[0020] An organ diagnostic apparatus may also be provided to producediagnostic data such as an organ viability index. The organ diagnosticapparatus includes features of an organ perfusion apparatus, such assensors and temperature controllers, as well as cassette interfacefeatures, and provides analysis of the organ and input and output fluidsin a perfusion system. Typically, the organ diagnostic apparatus is asimplified perfusion apparatus providing diagnostic data in a singlepass, in-line perfusion.

[0021] An organ viability index may be provided taking into account thevarious measured factors identified above, such as vascular resistance,pH etc. The index may be organ specific, or may be adaptable to variousorgans. The index compiles the monitored parameters into a diagnosticsummary to be used for making organ therapy decisions and decidingwhether to transplant the organ. The index may be automaticallygenerated and provided to the physician.

[0022] Embodiments of this invention include a control system forautomatically controlling perfusion of one or more organs by selectingbetween perfusion modes and control parameters. Automatic perfusion maybe based on sensed conditions in the system or manually inputparameters. The system may be preprogrammed or programmed during use.Default values and viability checks are utilized.

[0023] The perfusion apparatus may be used for various organs, such asthe kidneys, hearts, and lungs and may be adapted to more complexorgans, such as the liver, having multiple vasculature structures, forexample, the hepatic and portal vasculatures of the liver.

[0024] The present invention also provides an organ cassette whichallows an organ to be easily and safely moved between apparatus forperfusing, storing, analyzing and/or transporting the organ. The organcassette may be configured to provide uninterrupted sterile conditionsand efficient heat transfer during transport, recovery, analysis andstorage, including transition between the transporter, the perfusionapparatus and the organ diagnostic apparatus.

[0025] The present invention also provides an organ transporter whichallows for transportation of an organ over long distances. The organtransporter may be used for various organs, such as the kidneys, and maybe adapted to more complex organs, such as the liver, having multiplevasculature structures, for example, the hepatic and portal vasculaturesof the liver. The organ transporter includes features of an organperfusion apparatus, such as sensors and temperature controllers, aswell as cassette interface features.

[0026] The present invention focuses on avoiding damage to an organduring perfusion while monitoring, sustaining and/or restoring theviability of the organ and preserving the organ for storage and/ortransport and/or transplantation and/or other use. For various reasons,it may be decided that the organ should not be transplanted. Because ofthe difficulty in obtaining organs from donors and restoring theirviability, it is preferable that no organ should be completelydiscarded. As such, according to further exemplary embodiments of thisinvention, even though an organ might not be suitable for transplanting,the same organ can be used for other purposes such as screening theorgan with bioactive agents for drug research or the like.

[0027] According to exemplary embodiments of the invention, theperfusion, diagnostic and transporter apparatus of the invention may beused in conjunction with the above techniques and methods and/or inconjunction with further techniques and methods, to perform researchwith an organ or tissue. Except where otherwise specified, organ in thepresent application includes tissue. During the period in which theorgan is preserved and/or maintained, various drug research anddevelopment activities may be performed on and/or with the organ. Theorgan may be perfused with a medical fluid which may contain a substancesuch as a drug or other bioactive agent or other test substance, toobtain data regarding the interaction of the medical fluid and/or thesubstance and the organ. The data may then be used to provideinformation regarding efficacy, toxicity or other properties of thesubstance, for example in support of regulatory filings for new drugs ornew uses thereof.

[0028] The perfusion, diagnostic and/or transporter apparatus may beused to perfuse a medical fluid through an organ while monitoring theorgan and the organ outflow to analyze the condition of the organ and/orto determine the effect on it from the introduction of the medical fluidand/or substance such as a drug or other bioactive agent.

[0029] The data of the organ, the medical fluid and the interactiontherebetween can be compiled. Additionally, an organ data index may beprovided to be used for storing the data generated from perfusing theorgan. The data allows for ready research of organ and medical fluid andinformation may also be directly recovered from the perfusion,diagnostic or transporter apparatus to monitor the organ status. Varioustypes of data and information may be grouped into sub-records orsub-directories to assist in data management and transfer. All thesub-records may be combined to form an overall organ screening record,which may be disseminated to or retrievable by physicians, scientists orother organizations for research purposes.

[0030] The perfusion apparatus, transporter, cassette, and organdiagnostic apparatus may be networked to permit remote management,tracking and monitoring of the location and therapeutic and diagnosticparameters of the organ or organs being stored or transported. Theinformation systems may be used to compile historical data of organtransport and storage, and provide cross-referencing with hospital andUnited Network for Organ Sharing (UNOS) data on the donor and recipient.The systems may also provide outcome data to allow for ready research ofperfusion parameters and transplant outcomes.

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] These and other aspects and advantages of the invention willbecome apparent from the following detailed description of embodimentswhen taken in conjunction with the accompanying drawings, in which:

[0032]FIG. 1 is an organ perfusion apparatus according to the invention;

[0033]FIG. 2 is a schematic diagram of the apparatus of FIG. 1;

[0034]FIG. 3 is a diagram of the electronics of the apparatus of FIG. 1;

[0035]FIG. 4 is an exploded view of a first pump module of a combinedpump, filtration, oxygenation and/or debubbler apparatus according tothe invention;

[0036]FIG. 5 is an exploded view of a filtration module of a combinedpump, filtration, oxygenation and/or debubbler apparatus according tothe invention;

[0037]FIG. 6 is an exploded view of an oxygenation module of a combinedpump, filtration, oxygenation and/or debubbler apparatus according tothe invention;

[0038]FIG. 7 is an exploded view of a debubbler module of a combinedpump, filtration, oxygenation and/or debubbler apparatus according tothe invention;

[0039]FIG. 8 is an exploded view of a second pump module of a combinedpump, filtration, oxygenation and/or debubbler apparatus according tothe invention;

[0040]FIG. 9 is an exploded perspective view showing the modules ofFIGS. 4-8 assembled together;

[0041]FIG. 10 is a front perspective view of an assembled modularcombined pump, filtration, oxygenation and/or debubbler apparatusaccording to the invention;

[0042]FIGS. 11A-11D show side perspective views of various embodimentsof an organ cassette according to the invention;

[0043]FIG. 12 is a schematic diagram of an organ perfusion apparatusconfigured to simultaneously perfuse multiple organs;

[0044]FIGS. 13A and 13B show a stepping motor/cam valve according to theinvention;

[0045]FIGS. 14A-14F show another stepping motor/cam valve according tothe invention;

[0046]FIG. 15 shows a block diagram that schematically illustrates acontrol system according to the invention;

[0047]FIG. 16 shows an exemplary diagram of possible processing stepsaccording to the invention;

[0048]FIGS. 17 and 17A show an embodiment of an organ cassette of thepresent invention;

[0049]FIGS. 18 and 18A show an embodiment of an organ chair according tothe present invention;

[0050]FIG. 19 shows an exterior perspective view of an organ transporteraccording to the present invention;

[0051]FIG. 20 shows a cross-section view of an organ transporter of FIG.19;

[0052]FIG. 21 shows a block diagram of an organ transporter of FIG. 19;

[0053]FIG. 22 shows operation states of an organ transporter of FIG. 19;

[0054]FIG. 23 shows an alternative cross-section view of an organtransporter of FIG. 19;

[0055]FIG. 24 shows data structures and information transfer schemes ofa perfusion and organ transplant system of the present invention;

[0056]FIGS. 25 and 25A show motor control of a perfusion pump accordingto the present invention;

[0057]FIG. 26 shows a liver perfusion apparatus according to the presentinvention;

[0058]FIG. 27 shows a close-up view of a peristaltic pump for use in aperfusion apparatus according to FIG. 26;

[0059]FIG. 28 shows an overall view of an organ diagnostic systemaccording to the present invention;

[0060]FIG. 29 shows a perspective view of an organ evaluation instrumentfor use in an organ diagnostic system according to FIG. 28;

[0061]FIG. 30 shows an in-line perfusion system for use in an organdiagnostic system according to FIG. 28; and

[0062]FIG. 31 shows a logic circuit for an organ diagnostic systemaccording to FIG. 28.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0063] For a general understanding of the features of the invention,reference is made to the drawings. In the drawings, like referencenumerals have been used throughout to designate like elements.

[0064]FIG. 1 shows an organ perfusion apparatus 1 according to theinvention. FIG. 2 is a schematic illustration of the apparatus ofFIG. 1. The apparatus 1 is preferably at least partially microprocessorcontrolled, and pneumatically actuated. The microprocessor 150connection to the sensors, valves, thermoelectric units and pumps of theapparatus 1 is schematically shown in FIG. 3. Microprocessor 150 andapparatus 1 may be configured to and are preferably capable of furtherbeing connected to a computer network to provide data sharing, forexample across a local area network or across the Internet.

[0065] The organ perfusion apparatus 1 is capable of perfusing one ormore organs simultaneously, at both normothermic and hypothermictemperatures (hereinafter, normothermic and hypothermic perfusionmodes). All medical fluid contact surfaces are preferably formed of orcoated with materials compatible with the medical fluid used, morepreferably non-thrombogenic materials. As shown in FIG. 1, the apparatus1 includes a housing 2 which includes front cover 4, which is preferablytranslucent, and a reservoir access door 3. The apparatus preferably hasone or more control and display areas 5 a, 5 b, 5 c, 5 d for monitoringand controlling perfusion.

[0066] As schematically shown in FIG. 2, enclosed within the housing 2is a reservoir 10 which preferably includes three reservoir tanks 15 a,15 b, 17. Two of the reservoir tanks 15 a, 15 b are preferably standardone liter infusion bags, each with a respective pressure cuff 16 a, 16b. A pressure source 20 can be provided for pressurizing the pressurecuffs 16 a, 16 b. The pressure source 20 is preferably pneumatic and maybe an on board compressor unit 21 supplying at least 10 LPM externalcuff activation via gas tubes 26,26 a,26 b, as shown in FIG. 2. Theinvention, however, is not limited to use of an on board compressor unitas any adequate pressure source can be employed, for example, acompressed gas (e.g., air, CO₂, oxygen, nitrogen, etc.) tank (not shown)preferably with a tank volume of 1.5 liters at 100 psi or greater forinternal pressurization. Alternatively, an internally pressurizedreservoir tank (not shown) may be used. Reservoir tanks 15 a, 15 b, 17may, in embodiments, be bottles or other suitably rigid reservoirs thatcan supply perfusate by gravity or can be pressurized by compressed gas.

[0067] Gas valves 22-23 are provided on the gas tube 26 to allow forcontrol of the pressure provided by the onboard compressor unit 21.Anti-back flow valves 24 a, 24 b may be provided respectively on the gastubes 26 a, 26 b. Pressure sensors P5, P6 may be provided respectivelyon the gas tubes 26 a, 26 b to relay conditions therein to themicroprocessor 150, shown in FIG. 3. Perfusion, diagnostic and/ortransporter apparatus may be provided with sensors to monitor perfusionfluid pressure and flow in the particular apparatus to detect faults inthe particular apparatus, such as pressure elevated above a suitablelevel for maintenance of the organ. Gas valves GV₁ and GV₂ may beprovided to release pressure from the cuffs 16 a, 16 b. One or both ofgas valves GV₁ and GV₂ may be vented to the atmosphere. Gas valve GV₄ incommunication with reservoir tanks 15 a, 15 b via tubing 18 a, 18 b maybe provided to vent air from the reservoir tanks 15 a, 15 b throughtubing 18. Tubing 18, 18 a, 18 b, 26, 26 a and/or 26 b may be configuredwith filters and/or check valves to prevent biological materials fromentering the tubing or from proceeding further along the fluid path. Thecheck valves and/or filters may be used to prevent biological materialsfrom leaving one organ perfusion tubeset and being transferred to thetubeset of a subsequent organ in a multiple organ perfusionconfiguration. The check valves and/or filters may also be used toprevent biological materials, such as bacteria and viruses, from beingtransferred from organ to organ in subsequent uses of the perfusionapparatus in the event that such biological materials remain in theperfusion apparatus after use. The check valves and/or filters preventcontamination problems associated with reflux in the gas and/or ventlines. For example, the valves may be configured as anti-reflux valvesto prevent reflux. The third reservoir tank 17 is preferably pressurizedby pressure released from one of the pressure cuffs via gas valve GV₂.

[0068] The medical fluid may be blood or a synthetic fluid and may, forexample, be a simple crystalloid solution, or may be augmented with anappropriate oxygen carrier. The oxygen carrier may, for example, bewashed, stabilized red blood cells, cross-linked hemoglobin, pegolatedhemoglobin or fluorocarbon based emulsions. The medical fluid may alsocontain antioxidants known to reduce peroxidation or free radical damagein the physiological environment and specific agents known to aid intissue protection. As discussed in detail below, an oxygenated (e.g.,cross-linked hemoglobin-based bicarbonate) solution is preferred for thenormothermic mode while a non-oxygenated (e.g., simple crystalloidsolution preferably augmented with antioxidants) solution is preferredfor the hypothermic mode. The specific medical fluids used in both thenormothermic and hypothermic modes are designed to reduce or prevent thewashing away of or damage to the vascular endothelial lining of theorgan. For the hypothermic perfusion mode, as well as for flush and/orstatic storage, a preferred solution is the solution disclosed in U.S.patent application Ser. No. 09/628,311, filed Jul. 28, 2000, the entiredisclosure of which is incorporated herein by reference. Examples ofadditives which may be used in perfusion solutions for the presentinvention are also disclosed in U.S. Pat. No. 6,046,046 to Hassanein,the entire disclosure of which is incorporated by reference. Of course,other suitable solutions and materials may be used, as is known in theart.

[0069] The perfusion solution may be provided in a perfusion solutionkit, for example, a saleable package preferably containing at least onefirst container holding a first perfusion solution for normothermicperfusion and at least one second container holding a second, differentperfusion solution for hypothermic perfusion, optionally the box 10shown in FIG. 2. The first perfusion solution may contain at least oneoxygen carrier, may be oxygenated and/or may be selected from the groupconsisting of a cross-linked hemoglobin and stabilized red blood cells.The second perfusion solution may be non-oxygenated, may contain atleast one anti-oxidant, and/or may contain at least one vasodilator.Additionally, the solution preferably contains no more than 5 mM ofdissolved pyruvate salt. Also, the first container and the secondcontainer may be configured to be operably connected to a perfusionmachine as perfusion fluid reservoirs in fluid communication withperfusate conduits of said perfusion machine. Further, one of the firstand second containers may be compressible to apply pressure to theperfusion solution therein. Furthermore, at least one of the first andsecond containers may include a first opening for passage of a containedperfusion solution out of the container and a second opening passage ofa compressed gas into the container. The package may be a cassetteconfigured to be operably connected to a perfusion machine forconnection of the first and second containers within the cassette influid communication with perfusate conduits or tubing of the perfusionmachine.

[0070] In other embodiments, the perfusion solution kit may contain atleast one first container holding a first perfusion solution forhypothermic perfusion at a first temperature and at least one secondcontainer holding a second, different perfusion solution for hypothermicperfusion at a second temperature lower than the first temperature. Inthe kit, the first perfusion solution may contain at least a crystalloidand may contain at least one vasodilator. The second perfusion solutionmay be oxygen carrier enhanced, where the oxygen carrier is selectedfrom the group consisting of a hemoglobin and stabilized red bloodcells. In addition, the second perfusion solution may, if desired,contain at least one anti-oxidant or free radical scavenger. Preferably,the second solution contains no more than 5 mM of dissolved pyruvatesalt. As above, the first container and the second container may beconfigured to be operably connected to a perfusion machine as perfusionfluid reservoirs in fluid communication with perfusate conduits of saidperfusion machine. Further, one of the first and second containers maybe compressible to apply pressure to the perfusion solution therein.Furthermore, at least one of the first and second containers may includea first opening for passage of a contained perfusion solution out of thecontainer and a second opening passage of a compressed gas into thecontainer. The package may be a cassette configured to be operablyconnected to a perfusion machine for connection of the first and secondcontainers within the cassette in fluid communication with perfusateconduits or tubing of the perfusion machine.

[0071] The medical fluid within reservoir 10 is preferably brought to apredetermined temperature by a first thermoelectric unit 30 a in heattransfer communication with the reservoir 10. A temperature sensor T3relays the temperature within the reservoir 10 to the microprocessor150, which adjusts the thermoelectric unit 30 a to maintain a desiredtemperature within the reservoir 10 and/or displays the temperature on acontrol and display areas 5 a for manual adjustment. Alternatively or inaddition, and preferably where the organ perfusion device is going to betransported, the medical fluid within the hypothermic perfusion fluidreservoir can be cooled utilizing a cryogenic fluid heat exchangerapparatus such as that disclosed in co-pending application Ser. No.09/039,443, which is hereby incorporated by reference.

[0072] An organ chamber 40 is provided which supports a cassette 65, asshown in FIG. 2, which holds an organ to be perfused, or a plurality ofcassettes 65,65,65, as shown in FIG. 12, preferably disposed oneadjacent the other. Various embodiments of the cassette 65 are shown inFIGS. 11A-11D. The cassette 65 is preferably formed of a material thatis light but durable so that the cassette 65 is highly portable. Thematerial may also be transparent to allow visual inspection of theorgan.

[0073] Preferably the cassette 65 includes side walls 67 a, a bottomwall 67 b and an organ supporting surface 66, which is preferably formedof a porous or mesh material to allow fluids to pass therethrough. Thecassette 65 may also include a top 67 d and may be provided with anopening(s) 63 for tubing (see, for example, FIG. 11D). The opening(s) 63may include seals 63 a (e.g., septum seals or o-ring seals) andoptionally be provided with plugs (not shown) to prevent contaminationof the organ and maintain a sterile environment. Also, the cassette 65may be provided with a closeable air vent 61 (see, for example, FIG.11D). Additionally, the cassette 65 may be provided with tubing forconnection to the organ or to remove medical fluid from the organ bathand a connection device(s) 64 for connecting the tubing to, for example,tubing 50 c, 81, 82, 91 and/or 132 (see, for example, FIG. 11D). Thecassette 65, and more particularly the organ support, opening(s),tubing(s) and/or connection(s), may be specifically tailored to the typeof organ and/or size of organ to be perfused. Outer edges 67 c of theside support walls 67 a can be used to support the cassette 65 disposedin the organ chamber 40. The cassette 65 may further include a handleportion 68 which allows the cassette 65 to be easily handled, as shown,for example, in FIGS. 11C and 11D. Each cassette 65 may also be providedwith its own stepping motor/cam valve 75 (for example, in the handleportion 68, as shown in FIG. 11C) for fine tuning the pressure ofmedical fluid perfused into the organ 60 disposed therein, discussed inmore detail below. Alternatively, pressure may, in embodiments, becontrolled by way of a pneumatic chamber, such as an individualpneumatic chamber for each organ (not shown), or by any suitablevariable valve such as a rotary screw valve or a helical screw valve.

[0074]FIG. 17 shows an alternative embodiment of cassette 65. In FIG.17, cassette 65 is shown with tubeset 400. Tubeset 400 can be connectedto perfusion apparatus 1 or to an organ transporter or an organdiagnostic apparatus, and allows cassette 65 to be moved between variousapparatus without jeopardizing the sterility of the interior of cassette65. Preferably, cassette 65 is made of a sufficiently durable materialthat it can withstand penetration and harsh impact. Cassette 65 isprovided with a lid, preferably two lids, an inner lid 410 and an outerlid 420. The lids 410 and 420 may be removable or may be hinged orotherwise connected to the body of cassette 65. Clasp 405 provides amechanism to secure lids 410 and 420 to the top of cassette 65. Clasp405 may additionally be configured with a lock to provide furthersecurity and stability. A biopsy port 430 may additionally be includedin inner lid 410 or both inner lid 410 and outer lid 420. Biopsy port430 provides access to the organ to allow for additional diagnosis ofthe organ with minimal disturbance of the organ. Cassette 65 may alsohave an overflow trough 440 (shown in FIG. 17A). Overflow trough 440 isa channel present in the top of cassette 65. When lids 410 and 420 aresecured on cassette 65, overflow trough 440 provides a region that iseasy to check to determine if the inner seal is leaking. Perfusate maybe poured into and out of cassette 65 and may be drained from cassette65 through a stopcock or removable plug.

[0075] Cassette 65 and/or both lids 410 and 420 may be constructed of anoptically clear material to allow for viewing of the interior ofcassette 65 and monitoring of the organ and to allow for video images orphotographs to be taken of the organ. Perfusion apparatus 1 or cassette65 may be wired and fitted with a video camera or a photographic camera,digital or otherwise, to record the progress and status of the organ.The captured images may be made available over a computer network suchas a local area network or the Internet to provide for additional dataanalysis and remote monitoring. Cassette 65 may also be provided with atag that would signal, e.g., through a bar code, magnetism, radiofrequency, or other means, the location of the cassette, that thecassette is in the apparatus, and/or the identity of the organ to theperfusion apparatus or transporter. Cassette 65 may be sterile packagedand/or may be packaged or sold as a single-use disposable cassette, suchas in a peel-open pouch. A single-use package containing cassette 65 mayalso include tubeset 400.

[0076] Cassette 65 may additionally be provided with an organ chair 1800shown in FIGS. 18 and 18A. Organ chair 1800 is removable and provides asupport surface for the organ within cassette 65. Utilizing a removableorgan chair 1800 allows the organ to be cannulated and secured undercold conditions when the organ is recovered from a donor before beingplaced into cassette 65. Organ chair 1800 may be reusable or single-use.Organ chair 1800 may be constructed specifically to correspond to eachtype of organ, such as the kidney, heart or liver. Organ chair 1800 ispreferably designed to be form fitting to the organ but to allow for thefull anthropometric range of organ sizes.

[0077] Preferably, organ chair 1800 is at least partially perforated toallow fluids to pass through organ chair 1800. The perforations in organchair 1800 may be sized to catch organ debris, or an additional filterlayer, preferably constructed of cloth, fabric, nylon, plastic, etc., tocatch organ debris of at least 15 microns in diameter. In addition, aseparate filter may be used on the tubing that intakes fluid directlyfrom the perfusate bath to prevent organ debris of a predetermined size,for example at least 10 to 15 microns in diameter, from entering theperfusion tubing.

[0078] Organ chair 1800 may also be configured with a venous outflowsampler 1810. Organ chair 1800 funnels the venous outflow into venousoutflow sampler 1810. Venous outflow sampler 1810 provides a readilyavailable source for capturing the venous outflow of the organ.Capturing the venous outflow in this manner permits analysis of theperfusate leaving the organ without cannulating a vein and enables organviability to be measured with a high degree of sensitivity by analyzingdifferentially the perfusate flowing into and out of the organ.Alternatively, venous outflow may be captured directly by cannulating avein, but this method increases the risk of damaging the vein or theorgan. Organ chair 1800 may also be raised and lowered within cassette65 to facilitate sampling from venous outflow sampler 1810.Alternatively, a sufficient amount of the organ bath may be drained fromcassette 65 to obtain access to venous outflow sampler 1810 or tocapture venous outflow before the outflow mixes with the rest of theperfusate in the organ bath.

[0079] Organ chair 1800 is preferably additionally configured with acannula 1820 that attaches to the perfused artery, such as the renalartery. Cannula 1820 may be reusable or may be suitable for single-use,preferably provided in a sterile package with cassette 65, organ chair1800 and tubeset 400. Cannula 1820 is provided with a cannula clamp 1830to secure cannula 1820 around the perfused artery and to preferablyprovide leak-tight perfusion. A straight-in flanged cannula may also beused, however clamping around the artery is preferable to preventcontact with the inner surface of the artery, which is easily damaged.Cannula 1820 may also be configured with additional branchingconnections for accessory arteries. Multiple cannula and cannula clampsizes may be used to accommodate various artery sizes or an adjustablecannula and cannula clamp may be used to accommodate various sizedarteries. Cannula clamp 1830 may be a clam-shell configuration or may bea two-part design. Cannula clamp 1830 may be configured with integral orseparate means for tightening cannula clamp 1830 to the proper pressureto provide leak-tight perfusion. In addition, cannula 1820 may beprovided with a snap 1840 to hold cannula 1820 closed. Cannula 1820 mayalso be provided with a vent 1850 to remove air bubbles from cannula1820.

[0080] Organ chair 1800 preferably has a detented region 1860 thatcorresponds to protrusions 1870 on cannula 1820. Such detents, tracks orgrooves on organ chair 1800 allow cannula 1820 to be positioned atseveral locations to provide various tensions on the perfused artery.This allows the ideal minimum tension to be set for each artery. Cannulaclamp 1830 secures the perfusate tubing to the perfused artery. Cannula1820 is adjustably secured to organ chair 1800 to provide forpositioning the perfused artery to accommodate variations in organ sizeand artery length to prevent stretching, twisting, sagging or kinking ofthe artery. The combination of organ chair 1800, cannula 1820 andadditional straps or wide belts provides a secure platform to transportthe organ and to transfer the organ between the cassette and thesurgical field.

[0081] Organ chair 1800, cannula 1820 and/or cannula clamp 1830 may beconstructed of an optically clear material to facilitate monitoring ofthe organ and perfusion status.

[0082] The cassette 65 is configured such that it may be removed fromthe organ perfusion apparatus 1 and transported to another organperfusion apparatus in a portable transporter apparatus, such as, forexample, a conventional cooler or a portable container such as thatdisclosed in simultaneously filed co-pending U.S. application Ser. No.09/161,919, or U.S. Pat. No. 5,586,438 to Fahy, which are herebyincorporated by reference in their entirety.

[0083] In embodiments, when transported, the organ is disposed on theorgan supporting surface 66 and the cassette 65 is preferably enclosedin a preferably sterile bag 69, as shown, for example, in FIG. 11A. Whenthe organ is perfused with medical fluid, effluent medical fluidcollects in the bag 69 to form an organ bath. Alternatively, thecassette 65 can be formed with a fluid tight lower portion in which theeffluent medical fluid may collect, or the effluent medical fluid maycollect in the organ chamber 40 to form the organ bath. In eitheralternative case, the bag 69 would preferably be removed prior toinserting the cassette into the organ chamber 40. Further, where aplurality of organs are to be perfused, an organ chamber may be providedfor each organ. Alternatively, cassette 65 can be transported in thedual-lid cassette of FIG. 17 and additionally carried within a portableorgan transporter.

[0084]FIG. 19 shows an external view of an embodiment of transporter1900 of the invention. The transporter 1900 of FIG. 19 has a stable baseto facilitate an upright position and handles 1910 for carryingtransporter 1900. Transporter 1900 may also be fitted with a shoulderstrap and/or wheels to assist in carrying transporter 1900. A controlpanel 1920 is preferably also provided. Control panel 1920 may displaycharacteristics, such as, but not limited to infusion pressure, poweron/off, error or fault condition, flow rate, flow resistance, infusiontemperature, bath temperature, pumping time, battery charge, temperatureprofile (maximums and minimums), cover open or closed, history log orgraph, and additional status details and messages, which are preferablyfurther transmittable to a remote location for data storage and/oranalysis. Flow and pressure sensors or transducers in transporter 1900may be used to calculate various organ characteristics including pumppressure and vascular resistance of an organ, which can be stored incomputer memory to allow for analysis of, for example, vascularresistance history, as well as to detect faults in the apparatus, suchas elevated pressure.

[0085] Transporter 1900 has latches 1930 that require positive useraction to open, thus avoiding the possibility that transporter 1900inadvertently opens during transport. Latches 1930 hold top 1940 inplace on transporter 1900. Top 1940 or a portion thereof may beconstructed with an optically clear material to provide for viewing ofthe cassette and organ perfusion status. Transporter 1900 may beconfigured with a cover open detector that monitors and displays if thecover is open or closed. Transporter 1900 may be configured with aninsulating exterior of various thicknesses to allow the user toconfigure transporter 1900 for varying extents and distances oftransport. In embodiments, compartment 1950 may be provided to holdpatient and organ data such as charts, testing supplies, additionalbatteries, hand-held computing devices and/or other accessories for usewith transporter 1900. Transporter 1900 may also be configured withmeans for displaying a UNOS label and/or identification and returnshipping information.

[0086]FIG. 20 shows a cross-section view of a transporter 1900.Transporter 1900 contains cassette 65 and pump 2010. Cassette 65 may beplaced into and taken out of transporter 1900 without disconnectingtubeset 400 from cassette 65, thus maintaining sterility of the organ.Sensors in transporter 1900 can detect the presence of cassette 65 intransporter 1900, and depending on the sensor, can read the organidentity from a barcode or radio frequency or other smart tag that maybe integral to cassette 65. This allows for automated identification andtracking of the organ and helps monitor and control the chain ofcustody. A global positioning system may be added to transporter 1900and/or cassette 65 to facilitate tracking of the organ. Transporter 1900can be interfaced to a computer network by hardwire connection to alocal area network or by wireless communication while in transit. Thisinterface allows perfusion parameters, vascular resistance, and organidentification and transporter and cassette location to be tracked anddisplayed in real-time or captured for future analysis.

[0087] Transporter 1900 also preferably contains a filter 2020 to removesediment and other particulate matter, preferably ranging in size from0.05 to 15 microns in diameter or larger, from the perfusate to preventclogging of the apparatus or the organ. Transporter 1900 also containsbatteries 2030, which may be located at the bottom of transporter 1900or beneath pump 2010 or at any other location that provides easy accessto change batteries 2030. Batteries 2030 may be rechargeable outside oftransporter 1900 or while intact within transporter 1900 and/or arepreferably hot-swappable one at a time. Batteries 2030 are preferablyrechargeable rapidly and without full discharge. Transporter 1900 mayalso provide an additional storage space 2040 at the bottom oftransporter 1900 for power cords, batteries and other accessories.Transporter 1900 may also include a power port for a DC hookup to avehicle such as an automobile or airplane and/or for an AC hookup.

[0088]FIG. 21 shows a block diagram of transporter 1900. Transporter1900 of FIG. 21 is intended to provide primarily hypothermic perfusion,and may operate at any temperatures, for example in the range of −25 to60° C., approximately 0 to 8° C., preferably approximately 4° C. Thetemperature may be adjusted based on the particular fluids used andadapted to the particular transport details, such as length of time oftransport. Transporter 1900 is cooled by coolant 2110, which may be anice and water bath or a cryogenic material. In embodiments usingcryogenic materials, the design should be such that organ freezing isprevented. The temperature of the perfusate bath surrounding the organis monitored by temperature transducer 2115. Transporter 1900 alsocontains filters 2020 to remove sediment and particulate, ranging insize from 0.05 to 15 microns in diameter or larger, from the perfusateto prevent clogging of the apparatus or the organ. Using a filter 2020downstream of pump 2010 allows for capturing inadvertent pump debris andalso dampens pressure spikes from pump 2010.

[0089] The flow of perfusate within transporter 1900 is controlled bypump 2010, which is preferably a peristaltic or roller pump. Pump 2010is preferably not in contact with the perfusate to help maintainsterility. In addition, tubeset 400 may be attached to pump 2010 withoutopening the tubing circuit. Pump 2010 is controlled by a computer ormicrocontroller. The computer can actively modulate the angular velocityof pump 2010 to reduce the natural pulse actions of pump 2010 to a lowlevel, resulting in essentially non-pulsatile flow. Further computercontrol can impose a synthesized pressure pulse profile that can besinusoidal or physiological or otherwise. The average flow rate andpressure can be made independent of pulse repetition rate by pulse widthmodulating or amplitude modulating the synthesized pressure pulses.Control over some or all of the pulse parameters can be made availableto users through control panel 1920 or over a network. Pulse control canbe organ specific. In the case of a liver, a single pump can providecontinuous flow to the portal vein at, for example, 1 to 3 liters perminute while providing pulsatile flow to the hepatic artery at, forexample, 100 to 300 ml per minute. Synchronizing the shunt valves to thepump controller allows independent pressure regulation of the two flows.

[0090] The flow of the perfusate into the organ is monitored by flowsensor 2125. Pressure transducers 2120 may be present to monitor thepressure the perfusate places on the tubing. Pressure transducers 2120may be used to monitor the pump pressure and/or the infusion pressure. Apressure transducer 2120 may be present just upstream of the organ tomonitor the organ infusion pressure. Transporter 1900 may be configuredwith a bubble detector 2125 to detect bubbles before the perfusateenters bubble trap 2130. Bubble detectors, such as bubble detector 2125,may be used to detect bubbles in, for example, the infuse line and/or inthe pump output line. Bubble trap 2130 removes air bubbles from theperfusate and vents the bubbles into the wash tube. Bubble trap 2130 maybe disposable and may be constructed integral to tubeset 400. Perfusateexiting bubble trap 2130 can either continue through infuse valve 2140or wash valve 2150. Wash valve 2150 is normally open and infuse valve2140 is normally closed. Preferably, wash valve 2150 and infuse valve2140 operate dependently in an on/off manner, such that if one valve isopen, the other valve is closed. Although infuse valve 2140 is normallyclosed, if the sensor and monitors all report suitable perfusionparameters present in transporter 1900, then infuse valve 2140 may beopened to allow organ perfusion. In the occurrence of a fault, such aselevated perfusion pressure above a suitable level for the organ, infusevalve 2140 switches back to closed and wash valve 2150 is opened todivert fluid flow into the perfusate bath surrounding the organ. Thisprovides a failsafe mechanism that automatically shunts perfusate flowand prevents organ perfusion in case of a power failure or computer orelectronics malfunction. A pressure transducer 2120, such as designatedby P₂, may be hardwired, redundant to the computer and software control,to wash valve 2150 and infuse valve 2140 to quickly deliver a defaultmessage to the valves in the case of a pressure malfunction. Inembodiments, the diverted fluid may be separately collected in anothercontainer or compartment.

[0091]FIG. 22 shows various operation states of transporter 1900. Forexample, using the controls provided on control panel 1920, a user mayselect operations such as perfuse, idle, wash and prime. FIG. 22 showsvarious options depending on the present state of transporter 1900. Thelabels idle, prime, wash, perfuse and error handling indicate the stateof transporter 1900 that is preferably displayed on control panel 1920during the corresponding operation. For example, when transporter 1900is in a wash operation, control panel 1920 displays the wash operationindicator, such as an LED display. The arrows connecting the variousoperations of transporter 1900 indicate the manual and automatic actionsthat may occur to transition transporter 1900 between operation states.Manual actions require the user to act, for example by pressing a buttonor turning a knob or dial. FIG. 22 exemplifies pressing a button orother indicator, for example, to move from a perfusion operation to anidle operation by pressing the stop button (Press Stop). To movedirectly into a perfuse operation from an idle operation, a user pressesthe perfuse button (Press Perfuse).

[0092] Automatic operations may be controlled by the passage of timeand/or by an internal monitor within transporter 1900. Such automaticoperation is shown in FIG. 22, for example, connecting the primeoperation to the idle operation. If the prime operation has beencompleted according to the internal transporter program parametersbefore the wash button has been pressed, transporter 1900 returns to anidle operation. Another automatic operation occurs during a perfuseoperation if a fault or error occurs, such as overpressurization of theorgan. When an error or fault occurs, transporter 1900 can move to anerror handling operation to determine the extent or degree of the faultor error. If the fault or error is determined to be a small orcorrectable error, transporter 1900 moves into a wash operation. Iftransporter 1900 can then adjust the system parameters to handle thefault or error, transporter 1900 moves back to perfuse (Error Recovery).If transporter 1900 can not adjust the system parameters to handle thefault or error, transporter 1900 moves to an idle operation. If theerror or fault detected is determined to be substantial, tranporter 1900may move directly into an idle operation.

[0093]FIG. 23 shows an alternative cross-section of transporter 1900.Transporter 1900 may have an outer enclosure 2310 constructed of metal,or preferably a plastic or synthetic resin that is sufficiently strongto withstand penetration and impact. Transporter 1900 containsinsulation 2320, preferably a thermal insulation made of, for example,glass wool or expanded polystyrene. Insulation 2320 may be variousthicknesses ranging from 0.5 inches to 5 inches thick or more,preferably 1 to 3 inches, such as approximately 2 inches thick.Transporter 1900 is cooled by coolant 2110, which may be, e.g., an iceand water bath or a cryogenic material. In embodiments using cryogenicmaterials, the design should be such that organ freezing is prevented.An ice and water mixture is preferably in an initial mixture ofapproximately 1 to 1, however, in embodiments the ice and water bath maybe frozen solid. Transporter 1900 can be configured to hold variousamounts of coolant, preferably up to 10 to 12 liters. An ice and waterbath is preferable because it is inexpensive and can not get cold enoughto freeze the organ. Coolant 2110 preferably lasts for a minimum of 6 to12 hours and more preferably lasts for a minimum of 30 to 50 hourswithout changing coolant 2110. The level of coolant 2110 may be viewedthrough a transparent region of transporter 1900 or may be automaticallydetected and monitored by a sensor. Coolant 2110 can be replaced withoutstopping perfusion or removing cassette 65 from transporter 1900.Coolant 2110 is maintained in a watertight compartment 2115 oftransporter 1900. Compartment 2115 prevents the loss of coolant 2110 inthe event transporter 1900 is tipped or inverted. Heat is conducted fromthe walls of the perfusion reservoir and cassette 65 into coolant 2110enabling control within the desired temperature range. Coolant 2110 is afailsafe cooling mechanism because transporter 1900 automaticallyreverts to cold storage in the case of power loss or electrical orcomputer malfunction. Transporter 1900 may also be configured with aheater to raise the temperature of the perfusate.

[0094] Transporter 1900 may be powered by batteries or by electric powerprovided through plug 2330. An electronics module 2335 is also providedin transporter 1900. Electronics module 2335 is cooled by vented airconvection 2370, and may further be cooled by a fan. Preferably,electronic module 2335 is positioned separate from the perfusion tubesto prevent the perfusate from wetting electronics module 2335 and toavoid adding extraneous heat from electronics module 2335 to theperfusate. Transporter 1900 has a pump 2010 that provides pressure toperfusate tubing 2360 to deliver perfusate 2340 to organ 2350.Transporter 1900 may be used to perfuse various organs such as a kidney,heart, liver, small intestine and lung. Transporter 1900 and cassette 65may accommodate various amounts of perfusate 2340, for example up to 3to 5 liters. Preferably, approximately 1 liter of a hypothermicperfusate 2340 is used to perfuse organ 2350. Organ 2350 may be variousorgans, including but not limited to a kidney, heart, lung, liver orsmall intestine.

[0095] Cassette 65 and transporter 1900 are preferably constructed tofit or mate such that efficient heat transfer is enabled. The geometricelements of cassette 65 and transporter 1900 are preferably constructedsuch that when cassette 65 is placed within transporter 1900, theelements are secure for transport.

[0096]FIG. 24 shows various data structures and information connectionsthat can be facilitated to assist in the overall communication and datatransfers that may be beneficial before, during and after organtransplantation. The perfusion apparatus, transporter, cassette, andorgan diagnostic apparatus may be networked to permit remote management,tracking and monitoring of the location and therapeutic and diagnosticparameters of the organ or organs being stored or transported. Theinformation systems may be used to compile historical data of organtransport and storage, and provide cross-referencing with hospital andUNOS data on the donor and any recipient and/or information on whytransplant my be innappropriate. The systems may also provide outcomedata to allow for ready research of perfusion parameters and transplantoutcomes. For example, information regarding the donor may be entered atthe location where an organ is recovered from a donor. Information mayalso be directly recovered from the perfusion, diagnostic or transporterapparatus to monitor organ status and location. Various types ofinformation may be grouped into sub-records or sub-directories to assistin data management and transfer. All the sub-records may be combined toform an overall transplant record, which may be disseminated to orretrievable by physicians, scientists or other organizations fortracking and monitoring purposes.

[0097] Preferred embodiments of transporter 1900 can automatically logmuch or all of the perfusion process data and transporter 1900 eventsinto an internal database. A radio frequency or barcode labeled tag orthe like for each cassette 65 allows transporter 1900 to reference thedata uniquely to each organ. When transporter 1900 reaches a dockingport, transporter 1900 can upload data to a main database computer overa LAN. Transporter 1900 can also provide real-time status whenevertransporter 1900 is connected to the LAN. Transporter 1900 can also beconfigured with a wireless communications setup to provide real-timedata transfer during transport. Perfusion apparatus 1 can also beconnected to the LAN and since perfusion apparatus is generallystationary, data uploads can occur continuously and in real-time. Thedata can be cross-referenced with UNOS data to utilize the UNOS data onorgan identification, donor condition, donor logistics, recipientlogistics and recipient outcomes. Data may be displayed and accessed onthe Internet to facilitate monitoring from any location.

[0098] Within the perfusion, diagnostic and/or transporter apparatus,the organ bath is preferably cooled to a predetermined temperature by asecond thermoelectric unit 30 b, as shown in FIG. 2, in heat transfercommunication with the organ chamber 40. Alternatively and preferablywhere the organ perfusion device is going to be transported, the medicalfluid within reservoir 10 can be cooled utilizing a heat transfer devicesuch as an ice and water bath or a cryogenic fluid heat exchangerapparatus such as that disclosed in co-pending application Ser. No.09/039,443, which is hereby incorporated by reference. A temperaturesensor T2 within the organ chamber 40 relays the temperature of theorgan 60 to the microprocessor 150, which adjusts the thermoelectricunit 30 b to maintain a desired organ temperature and/or displays thetemperature on the control and display areas 5 c for manual adjustment.

[0099] Medical fluid may be fed from the bag 15 a directly to an organ60 disposed in the organ chamber 40 through tubing 50 a, 50 b, 50 c orfrom bag 15 b through tubing 50 d, 50 e, 50 c by opening valve LV₄ orLV₃, respectively. Conventional medical fluid bag and tubing connectionsmay be utilized. All tubing is preferably disposable, easily replaceableand interchangeable. Further, all tubing is preferably formed of orcoated with materials compatible with the medical fluids used, morepreferably non-thrombogenic materials. An end of the tubing 50 c isinserted into the organ 60. The tubing may be connected to the organ(s)with conventional methods, for example, with sutures. The tubing mayinclude a lip to facilitate connection to the organ. Alternatively,cannula 1820 described above may be used with or without connection toan organ chair 1800. However, the specific methods and connection dependon the type of organs(s) to be perfused.

[0100] The microprocessor 150 preferably controls the pressure source 20in response to signals from the pressure sensor P1 to control thepressure of the medical fluid fed into the organ 60. The microprocessor150 may display the pressure on the control and display areas 5 a,optionally for manual adjustment. A fluid flow monitor F1 may also beprovided on the tubing 50 c to monitor the flow of medical fluidentering the organ 60 to indicate, for example, whether there are anyleaks present in the organ.

[0101] Alternatively, the medical fluid may be fed from the reservoirtank 17 via tubing 51 into an intermediary tank 70 preferably having apressure head of approximately 5 to 40 mm Hg. Medical fluid is then fedby gravity or, preferably, pressure, from the intermediary tank 70 tothe organ 60 along tubing 50 c by activating a valve LV₆. A level sensor71 may be provided in the intermediary tank 70 in order to maintain thepressure head. Where a plurality of organ chambers 40 and organs 60 areprovided, the organs 60 are connected in parallel to the reservoir 10utilizing suitable tubing duplicative of that shown in FIG. 2. See, forexample, FIG. 12. The use of pneumatically pressurized and gravity fedfluid pumps configured to avoid overpressurization even in cases ofsystem failure reduces or prevents general tissue damage to the organand the washing away of or damage to the vascular endothelial lining ofthe organ. Thus, organ perfusion in this system can be performed, e.g.,with either hydrostatic perfusion (gravity or pressure fed flow) orperistaltic perfusion by introducing flow to the organ from aperistaltic (roller) pump.

[0102] A bubble detection system may be installed to sense bubbles inthe perfusate. An air sensor and sensor board are preferably used. Theoutput of the sensor activates a debubbler system, such as an opensolenoid valve, to rid bubbles from the perfusate flow prior to organintroduction. As with all of the sensors and detectors in this system,the bubble detector may be positioned at any point in the system that iseffective based on the particular parameters or design characteristicsof the system. For example, a bubble detector and debubbler system BDmay be positioned between the cam valve 205 and pressure sensor P1, asshown in FIG. 1.

[0103] A stepping motor/cam valve 205, or other suitable variable valvesuch as a rotary screw valve, may be arranged on the tubing 50 c toprovide pulsatile delivery of the medical fluid to the organ 60, todecrease the pressure of the medical fluid fed into the organ 60, and/orto stop flow of medical fluid into the organ 60 if the perfusionpressure exceeds a predetermined amount. Alternatively, a flow diverteror shunt line may be provided in the perfusion apparatus to which thefluid flow is diverted in the occurrence of a fault, such as excesspressure, for example by opening and closing a valve or a series ofvalves. Specific embodiments of the stepping motor/cam valve are shownin FIGS. 13A-13B and 14A-14F. FIGS. 13A-13B show a steppingmotor/rotational type cam valve.

[0104]FIG. 13A is a top view of the apparatus. Tubing, for example,tubing 50 c, is interposed between a support 203 and cam 200. Cam 200 isconnected by a rod 201 to stepping motor 202. FIG. 13B is a side view ofthe apparatus. The dashed line shows the rotational span of the cam 200.In FIG. 13B, the cam 200 is in its non-occluding position. Rotated 180degrees, the cam 200 totally occludes the tubing 50 c with varyingdegrees of occlusion therebetween. This stepping motor/cam valve isrelatively fast, for example, with respect to the embodiment shown inFIGS. 14A-14F; however, it requires a strong stepping motor.

[0105]FIGS. 14A-14F disclose another stepping motor/cam valve 210according to the invention. FIG. 14A is a side view of the apparatuswhile FIG. 14C is a top view. Tubing, for example, tubing 50 c, isinterposed between cam 220 and support 223. The cam 220 is connected tostepping motor 222 by supports 221 a-221 d and helical screw 225, whichis connected to the stepping motor 222 via plate 222 a. FIG. 14B showsthe supports 221 a and plate 222 a in front view. As shown in FIG. 14D,where the support 221 d is to the left of the center of the helicalscrew 225, the tubing 50 c is not occluded. However, as the helicalscrew 225 is turned by the stepping motor 222, the support 221 d movesto the left (with respect to FIGS. 14D-14F) toward a position where thecam 220 partially or fully occludes the tubing 50 c. Such apparatus isslower than the apparatus of FIGS. 13A-13B, but is more energyefficient.

[0106] Medical fluid expelled from the organ 60 which has collected inthe bottom of the bag 69 (the cassette 65 or the organ chamber 40) iseither pumped out through tubing 81 by a pump 80 for filtration, passingthrough a filter unit 82 and being returned to the organ bath, or ispumped out by a pump 90 for circulation through tubing 91. The pumps 80,90 are preferably conventional roller pumps or peristaltic pumps;however, other types of pumps may also be appropriate.

[0107]FIG. 25 shows a simplified schematic of a pump and pulsecontroller 2500 and the interaction of the pump and pulse controllerwith a perfusion apparatus, such as shown in FIG. 1. Pump and pulsecontroller 2500 receives pressure sensor data input 2510 from pressuresensor P and tachometer data input 2520. A tachometer may be used to setthe phase angle of the active wave. Pump and pulse controller 2500converts this information to motor drive output 2530, which powers pump2540. FIG. 25A shows various modes of operation that pump and pulsecontroller 2500 can provide and how pump and pulse controller 2500eliminates pressure pulse waves from the perfusate flow and how itmodulates perfusate flow rate while maintaining a constant pressurepulse rate.

[0108] A peristaltic pump driven at a constant speed provides a constantpressure wave in the associated tubing. FIG. 25A shows in the first modeof operation the waveforms that result from a constant drive speedapplied to a peristaltic pump. The second mode of operation, calledactive continuous, shows how the pressure pulse wave can be eliminatedor canceled out by applying a motor drive wave that is opposite to thepressure wave of the pump. In the third mode of operation, called activewaveform amplitude modulating, the pump pressure pulse wave is canceledby the motor drive wave, and a selected wave is added with a newamplitude as compared to the original pressure pulse wave amplitude. Inthe fourth mode of operation, called active waveform pulse widthmodulating, the pump pressure pulse wave is canceled by the motor drivewave, and a selected wave is added with a new pulse width as compared tothe original pressure pulse wave width. In an alternative mode ofoperation, the frequency may be modulated by adding a new frequency waveto the canceled waves.

[0109] A level sensor L2 in communication with the microprocessor 150(see FIG. 3) ensures that a predetermined level of effluent medicalfluid is maintained within the organ chamber 40. As shown in FIG. 2, atemperature sensor T1 disposed in the tubing 91 relays the temperatureof the medical fluid pumped out of the organ bath along tubing 91 to themicroprocessor 150, which monitors the same. A pressure sensor P2disposed along the tubing 91 relays the pressure therein to themicroprocessor 150, which shuts down the system if the fluid pressure inthe tubing 91 exceeds a predetermined limit, or activates an alarm tonotify the operator that the system should be shut down, for example, toclean filters or the like.

[0110] As the medical fluid is pumped along tubing 91 it preferablypasses through a filter unit 95 (e.g., 25μ, 8μ, 2μ, 0.8μ, 0.2μ, and/or0.1μ filters); a CO₂ scrubber/O₂ membrane 100 and an oxygenator 110, forexample, a JOSTRA™ oxygenator. The CO₂ scrubber/O₂ membrane 100 ispreferably a hydrophobic macroporous membrane with a hydrophilic (e.g.,Hypol) coating in an enclosure. A vacuum source (not shown) is utilizedto apply a low vacuum on a side opposite the hydrophilic coating by theactivation of valve VV₁. A hydrostatic pressure of approximately 100 mmHg is preferred for aqueous passage through the membrane. The mechanicalrelief valve (not shown) prevents the pressure differential fromattaining this level. Immobilized pegolated carbonic anhydrase may beincluded in the hydrophilic coating. This allows bicarbonate to beconverted to CO₂ and subsequently removed by vacuum venting. However,with organs such as kidneys which have the ability to eliminatebicarbonate, this may be unnecessary except in certain cases.

[0111] The oxygenator 110 is preferably a two stage oxygenator whichpreferably includes a hydrophilically coated low porosity oxygenpermeable membrane. A portion of the medical fluid is diverted aroundthe oxygenator along tubing 111 in which is disposed a viability sensorV1, which senses fluid characteristics, such as organ resistance(pressure/flow), pH, pO₂, pCO₂, LDH, T/GST, Tprotein, lactate, glucose,base excess and ionized calcium levels indicative of an organ'sviability. The viability sensor V1 is in communication with themicroprocessor 150 and allows the organ's viability to be assessedeither automatically or manually. One of two gases, preferably 100%oxygen and 95/5% oxygen/carbon dioxide, is placed on the opposite sideof the membrane depending on the pH level of the diverted medical fluid.Alternatively, another pump (not shown) may be provided which pumpseffluent medical fluid out of the organ chamber 40 and through aviability sensor before returning it to the bath, or the viabilitysensor can be placed on tubing 81 utilizing pump 80. In embodiments, thefluid characteristics may be analyzed in a separate diagnostic apparatusand/or analyzer as shown in FIGS. 28-31.

[0112] The sensed fluid characteristics, such as organ resistance(pressure/flow), pH, pO₂, pCO₂, LDH, T/GST, Tprotein, lactate, glucose,base excess and ionized calcium levels may be used to analyze anddetermine an organ's viability and/or the effect of applied bioactive orother test substance thereon. The characteristics may be analyzedindividually or multiple characteristics may be analyzed to determinethe effect of various factors. The characteristics may be measured bycapturing the venous outflow of the organ and comparing its chemistry tothe perfusate inflow. The venous outflow may be captured directly andmeasured or the organ bath may be measured to provide a roughapproximation of the fluid characteristics for comparisons over a periodof time.

[0113] In embodiments, an organ viability index is provided taking intoaccount the various measured factors identified above, such as vascularresistance, pH, etc. The index may be organ specific, or may beadaptable to various organs. The index compiles the monitored parametersinto a diagnostic summary which may be used for making organ therapydecisions and deciding whether to transplant the organ or make other useof it. The index may be automatically generated and provided to thephysician. The index is preferably computer generated via a connectionto the perfusion apparatus, transporter, cassette and/or organdiagnostic apparatus. The additional information, such as donor specificinformation, may be entered into a single computer at the site of theperfusion apparatus, transporter, cassette and/or organ diagnosticapparatus or may be entered in a remote computer and linked to theperfusion apparatus, etc. In embodiments, the index may be madeavailable over a computer network such as a local area network or theInternet for quick comparison, remote analysis and data storage.

[0114] The organ viability index provides measurements and normal rangesfor each characteristic, such as vascular resistance and perfusatechemistry characteristics based on pH, pO₂, pCO₂, LDH, T/GST, Tprotein,lactate, glucose, base excess and ionized calcium levels. For example,at approximately 5° C., normal pH may be from 7.00 and 8.00, preferablyfrom 7.25 and 7.75 and more preferably from 7.50 and 7.60 and baseexcess may be in the range of from −10 to −40, preferably from −15 to−30, and more preferably from −20 to −25. Measurements that are outsidethe normal range may be indicated visually, e.g., by an asterisk orother suitable notation, aurally or by machine perceivable signals. Thecharacteristics give the physician insight into the metabolism of theorgan, such as stability of the metabolism, consumption of glucose,creation of lactic acid and oxygen consumption.

[0115] The index may also provide identifying information, such as age,gender, blood type of the donor and any expanded criteria; organinformation, such as organ collection date and time, warm ischemia time,cold ischemia time and vascular resistance; apparatus information, suchas flow rate, elapsed time the pump has been operating and pressure; andother identifiers such as UNOS number and physician(s) in charge. Theindex may additionally provide temperature corrections if desired.

[0116] Returning to FIG. 2 and the flow and/or treatment of the medicalfluid or perfusate in perfusion apparatus 1, alternative to the pump 90,filter unit 95, the CO₂ scrubber/O₂ membrane 100 and/or the oxygenator110, a modular combined pump, filtration, oxygenation and/or debubblerapparatus may be employed such as that described in detail insimultaneously filed co-pending U.S. patent application Ser. No.09/039,318, which is hereby incorporated by reference. As shown in FIGS.4-10, the apparatus 5001 is formed of stackable modules. The apparatus5001 is capable of pumping a fluid through a system as well asoxygenating, filtering and/or debubbling the fluid. The modules are eachformed of a plurality of stackable support members and are easilycombinable to form a compact apparatus containing desired components.Filtration, oxygenation and/or degassing membranes are disposed betweenthe support members.

[0117]FIGS. 4-8 show various modules that may be stacked to form acombined pump, filtration, oxygenation and/or debubbler apparatus, suchas the combined pump, filtration, oxygenation and debubbler apparatus5001 shown in FIGS. 9-10. As depicted in these figures, the combinedpump, filtration, oxygenation and debubbler apparatus 5001 is preferablyformed of a plurality of stackable support members groupable to form oneor more modules.

[0118] Interposed between the plurality of stackable support member arefiltration, oxygenation and/or degassing membranes depending on aparticular user's needs. The filtration, oxygenation and/or degassingmembranes are preferably commercially available macro-reticularhydrophobic polymer membranes hydrophilically grafted in a commerciallyknown way, such as, for example, ethoxylation, to prevent proteindeprivation, enhance biocompatibility with, for example, blood and toreduce clotting tendencies. The filtration membrane(s) is preferablyhydrophilically grafted all the way through and preferably has aporosity (pore size) within a range of 15 to 35μ, more preferably 20 to30μ, to filter debris in a fluid, preferably without filtering outcellular or molecular components of the fluid. The degassing membrane(s)and oxygenation membrane(s) are hydrophilically surface treated tomaintain a liquid-gas boundary. The degassing membrane(s) andoxygenation membrane(s) preferably have a porosity of 15μ or less, morepreferably 10μ or less.

[0119] The modules may include a first pump module 5010, as shown inexploded view in FIG. 4; a filtration module 5020, as shown in explodedview in FIG. 5; an oxygenation module 5030, as shown in exploded view inFIG. 6; a debubbler module 5040, as shown in exploded view in FIG. 7;and a second pump module 5050, as shown in exploded view in FIG. 8. Thepump modules are each connected to a source of pump fluid and areactuated either manually or by the microprocessor. The support membersare preferably similarly shaped. For example, the support members mayeach be plate-shaped; however, other shapes may also be appropriate. Asshown in FIG. 10, the support members are preferably removably connectedby screws or bolts 5065; however, other fasteners for assembling theapparatus may also be appropriate.

[0120] The first pump module 5010 preferably includes a first (end)support member 5011, a second support member 5012 with a cut-out centerarea 5012 c, a diaphragm 5013 and a third support member 5014. Thesupport members of this module and each of the other modules arepreferably thin and substantially flat (plate-like), and can be formedof any appropriate material with adequate rigidity and preferably alsobiocompatibility. For example, various resins and metals may beacceptable. A preferred material is an acrylic/polycarbonate resin.

[0121] The first (end) support member 5011 is preferably solid andprovides support for the pump module 5010. The first (end) supportmember 5011 preferably includes a domed-out cavity for receiving pumpfluid such as air. Tubing 5011 t is provided to allow the pump fluid toenter the pump module 5010. The diaphragm 5013 may be made of anysuitable elastic and preferably biocompatible material, and ispreferably polyurethane. The third support member 5014 includes adomed-out fluid cavity 5014 d and tubing 5014 t for receiving fluid,such as, for example, blood or an artificial perfusate, into the cavity5014 d of the pump module 5010. The first pump module, or any of theother modules, may also include a port 5014 p for sensors or the like.Preferably hemocompatible anti-backflow valves serve to allowunidirectional flow through the pump module 5010.

[0122] The filtration module 5020 preferably includes a filtrationmembrane 5021 m which forms a boundary of cavity 5014 d, a first supportmember 5022 with a cut-out center area 5022 c, a degassing membrane 5022m and second and third support members 5023 and 5024. The filtrationmembrane 5021 m is preferably a 25μ macro-reticular filtration membranemodified to enhance biocompatibility with, for example, blood and toreduce clotting tendencies (like the other supports, filters andmembranes in the device). The degassing membrane 5022 m is preferably a0.2-3μ macro-reticular degassing membrane with a reverse flow aqueouspressure differential of at least 100 mmHg for CO₂ removal surfacemodified to enhance biocompatibility.

[0123] The first support 5022 includes tubing 5022 t for forwardingfluid into the oxygenation module 30, or another adjacent module, ifapplicable, after it has passed through the filtration membrane 5021 mand along the degassing membrane 5022 m. The second support member 5023of the filtration module 5020 includes a domed-out fluid cavity 5023 dand tubing 5023 t through which a vacuum may be applied to the cavity5023 d to draw gas out of the fluid through degassing membrane 5022 m.The fourth support member 5024 is preferably solid and provides supportfor the filtration module 5020. The third support member can alsoinclude tubing 5024 t through which a vacuum may be applied to draw gasout of the fluid through the degassing membrane 5031 m of theoxygenation module 5030 as discussed below. The filtration module 5020,or any of the other modules, may also include a port 5023 p for sensorsor the like.

[0124] The oxygenation module 5030 includes a degassing membrane 5031 m,a first support member 5032, a filtration membrane 5033 m, anoxygenation membrane 5034 m, a second support member 5034 with a cut-outcenter area 5034 c, and third and fourth support members 5035, 5036. Thedegassing membrane 5031 m is preferably a 0.2-3μ macro-reticulardegassing membrane with a reverse flow aqueous pressure differential ofat least 100 mmHg surface modified to enhance biocompatibility.

[0125] The first support member 5032 includes a domed-out fluid cavity5032 d. The surface of the domed-out fluid cavity 5032 d preferablyforms a tortuous path for the fluid, which enhances the oxygenation anddegassing of the fluid. The filtration membrane 5033 m is preferably a25μ macro-reticular filtration membrane modified to enhancebiocompatibility. The oxygenation membrane 5034 m is preferably a 0.2-1μmacro-reticular oxygenation membrane with a reverse flow aqueouspressure differential of at least 100 mmHg surface modified to enhancebiocompatibility.

[0126] The second support member 5034 includes tubing 5034 t forforwarding fluid out of the oxygenation module 5030 into the debubblermodule 5040, or another adjacent module, if applicable. The thirdsupport member 5035 includes a domed-out cavity 5035 d and tubing 5035 tfor receiving oxygen from an external source. The fourth support member5036 is preferably solid and provides support for the oxygenation module5030.

[0127] The debubbler module 5040 includes a first support member 5041, afiltration membrane 5042 m, a degassing membrane 5043 m, a secondsupport member 5043 having a cut-out center area 5043 c, and a thirdsupport member 5044. The first support member 5041 has a domed-out fluidcavity 5041 d.

[0128] The filtration membrane 5042 m is preferably a 25μmacro-reticular filtration membrane modified to enhancebiocompatibility. The degassing membrane 5043 m is preferably a 0.2-3μmacro-reticular degassing membrane with a reverse flow aqueous pressuredifferential of at least 100 mmHg surface modified to enhancebiocompatibility. The second support member 5043 has tubing 5043 t forforwarding fluid out of the debubbler module 5040 into the pump module5050, or another adjacent module, if applicable. The third supportmember 5044 includes a domed-out cavity 5044 d and tubing 5044 t throughwhich a vacuum may be applied to draw gas out of the fluid through thedegassing membrane 5043 m.

[0129] The second pump module 5050 may correspond to the first pumpmodule 5010. It preferably includes a first support member 5051, adiaphragm 5052, a second support member 5053 with a cut-out center area5053 c, and a third (end) support member 5054. The first support member5051 includes a domed out fluid cavity 5051 d and tubing 5051 t forallowing fluid to exit the pump module. The diaphragm 5052 is preferablya polyurethane bladder.

[0130] The third (end) support piece member 5054 is preferably solid andprovides support for the pump module 5050. Support member 5054preferably includes a domed out cavity (not shown) for receiving pumpfluid. Tubing 5054 a is provided to allow the pump fluid such as air toenter the pump module 5050. Preferably hemocompatible anti-backflowvalves may serve to allow unidirectional flow through the pump module5050.

[0131] In operation, blood and/or other medical fluid enters the firstpump module 5010 through tube 5014 t passes through the filtrationmembrane 5021 m and along the degassing membrane 5022 m. A small vacuumis applied through tubing 5023 t to draw gas through the degassingmembrane 5022 m. Next, the blood and/or medical fluid travels into theoxygenation module 5030 via internal tubing 5022 t, passing along thedegassing membrane 5031 m, through the filtration membrane 5033 m andalong the oxygenation membrane 5034 m. Oxygen is received into thedomed-out cavity 5035 d of the third support member of the oxygenationmodule 5030 via tubing 5035 t and passes through the oxygenationmembrane 5034 m into the blood and/or other medical fluid as the bloodand/or other medical fluid travels along its surface.

[0132] After being oxygenated by the oxygenation module 5030, the bloodand/or other medical fluid then travels via internal tubing 5034 t intothe debubbler module 5040. The blood and/or other medical fluid passesthrough the filtration membrane 5042 m and along the degassing membrane5043 m. A small vacuum force is applied through tubing 5044 t to drawgas out of the blood and/or other medical fluid through the degassingmembrane 5043 m. After passing through the degassing module 5040, theblood and/or other medical fluid travels into the second pump module5050 through tubing 5041 t, and exits the second pump module 5050 viatubing 5051 t.

[0133] After passing through the oxygenator 110, or alternativelythrough the combined pump, oxygenation, filtration and/or degassingapparatus 5001, the recirculated medical fluid is selectively eitherdirected to the reservoir 15 a or 15 b not in use along tubing 92 a or92 b, respectively, by activating the respective valve LV₂ and LV₅ onthe tubing 92 a or 92 b, or into the organ chamber 40 to supplement theorgan bath by activating valve LV₁. Pressure sensors P3 and P4 monitorthe pressure of the medical fluid returned to the bag 15 a or 15 b notin use. A mechanical safety valve MV₂ is provided on tubing 91 to allowfor emergency manual cut off of flow therethrough. Also, tubing 96 andmanual valve MV₁ are provided to allow the apparatus to be drained afteruse and to operate under a single pass mode in which perfusate exitingthe organ is directed to waste rather than being recirculated(recirculation mode.)

[0134] A bicarbonate reservoir 130, syringe pump 131 and tubing 132, andan excretion withdrawal unit 120, in communication with a vacuum (notshown) via vacuum valve VV₂, and tubing 121 a, 122 a are also eachprovided adjacent to and in communication with the organ chamber 40.

[0135] The present invention also provides for perfusion apparatusadapted for organs with complex vasculature structures, such as theliver. Using the liver as an example, FIG. 26 shows perfusion apparatus2600. Perfusion apparatus 2600 has a single pump 2610, which ispreferably a roller pump or peristaltic pump. The tubing splits into twoor more directions with, for example, three tubes going toward theportal vein side of the liver (portal tubing 2625) and one tube goingtoward the hepatic artery side of the liver (hepatic tubing 2626). Theportal side of perfusion apparatus 2600 has more tubes because theportal side of the liver uses three to ten times the flow that thehepatic side uses. FIG. 27 shows a perspective view of pump 2610 and thetubing split into portal tubing 2625 and hepatic tubing 2626.

[0136] Both the portal side and the hepatic side of perfusion apparatus2600 preferably have a filter 2630, bubble trap 2640, pressuretransducer 2650, temperature transducer 2660, and flow sensor 2670. Anadditional temperature transducer 2660 may be present in fluid returntubing 2620. The organ may be cooled as discussed above, for example byan ice and water bath 2680 or by a cryogenic fluid. In embodiments usingcryogenic fluids, the design should be such that organ freezing isprevented.

[0137] Multiple pumps may be used; however, utilizing multiple pumpsgenerally increases the size and cost of the apparatus. Utilizing asingle pump 2610 for both vasculature systems provides a variety ofmodes that can be used to perfuse a liver. After each bubble trap 2640,the tubing splits into two directions. On the hepatic side, hepaticinfusion valve 2685 controls the flow to the hepatic side of the liverand hepatic wash valve 2686 controls the flow into the organ bath. Onthe portal side, portal infusion valve 2695 controls the flow to theportal side of the liver and portal wash valve 2696 controls the flowinto the organ bath. Preferably, each pair of infusion valves and washvalves operates in an on/off or either/or manner. In other words, when,for example, the portal side is set to infuse, the portal wash valve2696 is closed. The following table shows various modes of operation forperfusion apparatus 2600. MODES OF PORTAL HEPATIC DOMINANT OPERATIONVALVES VALVES PRESSURE NOTES Portal Only Infuse Wash Portal No hepaticperfusion Portal Priority Infuse Infuse Portal Hepatic slave to portalHepatic Only Wash Infuse Hepatic No portal perfusion Hepatic PriorityInfuse Infuse Hepatic Portal slave to hepatic Alternating InfuseSwitching Alternating Wavy portal flow; pulsed hepatic flow

[0138] The modes of operation identified in the table above show optionsfor infusing a liver. In the first mode, Portal Only, the portal side ofthe liver is infused. Therefore, the portal valves are set to infuse,which means that portal infusion valve 2695 is open and portal washvalve 2696 is closed. Also, in a Portal Only mode, hepatic infusionvalve 2685 is closed and hepatic wash valve 2686 is open. In a PortalOnly mode, the portal pressure is dominant, which means the pressure iscontrolled by the pressure transducer 2650 on the portal side. In thismode, there is no hepatic infusion.

[0139] In a Portal Priority mode, the portal valves and the hepaticvalves are set to infuse. The portal pressure is dominant; andtherefore, the hepatic side is a slave to the portal side. In anAlternating mode, the portal valves are set to infuse and the hepaticvalves switch between an infuse setting and a wash setting. In anAlternating mode, when the hepatic valves are set to infuse, the hepaticside provides the dominant pressure. When the hepatic valves are set towash, the portal side provides the dominant pressure. This type ofalternating pressure control provides the portal side with a wavy flowand provides the hepatic side with a pulsed flow.

[0140] The present invention also provides an organ diagnostic system2800 shown in FIG. 28. Organ diagnostic system 2800 has a computer 2810and an analyzer 2820. Connected to both computer 2810 and analyzer 2820is an organ evaluation instrument 2830, also shown in FIG. 29. Organdiagnostic system 2800 is preferably provided with suitable displays toshow the status of the system and the organ. Organ evaluation instrument2830 has a perfusate chamber 2840 and an organ chamber 2850. Connectinganalyzer 2820 and organ evaluation instrument 2830 is a transfer line2860. Organ diagnostic system 2800 provides analysis of an organ andproduces an organ viability index quickly and in a sterile cassette,preferably transferable from perfusion apparatus 1 and/or transporter1900. The organ viability index is preferably produced by flow andtemperature programmed single-pass perfusion and in-line automaticanalysis. The analysis may be performed in a multi-pass system. Themulti-pass system will recirculate the flow for analysis whilesustaining and evaluating the organ. Flow may be controlled by a valve(not shown) and may recirculate back to the beginning of the systemprior to reaching the analyzer 2820.

[0141] A beneficial aspect of the single-pass system is that it can beconfigured with a limited number of sensors and requires only enoughperfusate to perform the analysis. Single-pass perfusion also allows foran organ inflow with a perfusate having a known and predeterminedchemistry. This increases the flexibility of types and contents ofperfusates that may be delivered such as blood or a synthetic bloodcarrier or a combination thereof, which can be tailored and modified tothe particular analysis in process.

[0142]FIG. 29 shows a perspective view of organ evaluation instrument2830. Organ evaluation instrument 2830 has a perfusate chamber 2840 andan organ chamber 2850. Organ chamber 2850 may be insulated andpreferably has a lid 2910 that may be removable or may be hinged. Organchamber 2850 is preferably configured to receive cassette 65, preferablywithout opening cassette 65 or jeopardizing the sterility of theinterior of cassette 65. Cassette 65 and organ chamber 2850 arepreferably constructed to fit or mate such that efficient heat transferis enabled. The geometric elements of cassette 65 and organ chamber 2850are preferably constructed such that when cassette 65 is placed withinorgan chamber 2850, the elements are secure for analysis. A port 2920 isalso provided to connect transfer line 2860.

[0143]FIG. 30 shows a single-pass fluid system of organ diagnosticsystem 2800. The initial perfusion fluids 3000 are contained in achamber 3010. Chamber 3010 is preferably temperature controlled by aheating and cooling system. Fluid flow within the system is monitored byflow sensor 3020 and controlled by signaling to pinch valves 3030 andpumps 3040. The fluid system also provides a bubble trap 3050, apressure transducer 3060 and a temperature transducer 3070. Heatexchanger 3080 provides temperature control and heating and cooling tothe fluid within the system prior to organ perfusion. The organ isperfused in cassette 65. The fluid in the organ bath may be collected,or the venous outflow may be captured, to be analyzed. The fluid iscollected and passed via transfer line 2860 to analyzer 2820. Transferline 2860 may also be provided with a separate heating and cooling unit.After the fluid is analyzed, it may be collected in a waste receptacle3090.

[0144]FIG. 31 shows a logic circuit for organ diagnostic system 2800.The computer provides control parameters and receives results and datafrom the analyzer. The logic circuit shows inputs from the sensors tothe microcontroller and outputs to hardware elements, such as perfusatecoolers, perfusate heaters, pinch valves, pumps, transferlineheater/cooler and displays.

[0145] The method according to the invention preferably utilizesapparatus such as that discussed above to perfuse an organ to sustain,monitor and/or restore the viability of an organ and/or to transportand/or store the organ. Preservation of the viability of an organ isimportant to a successful organ transplant or other use of the organ.Organs are often deprived of oxygen (known as ischemia) for extendedperiods of time due to disease or injury to the donor body, duringremoval of the organ from the donor body and/or during storage and/ortransport of the organ. The perfusion, diagnostic, and/or transporterapparatus of the present invention have the ability to detect the cellchemistry of an organ to be transplanted in order to adjust theperfusate and control the cellular metabolism to repair ischemic damageto the organ and to prevent reperfusion injury. One specific outcome ofischemic injury may be apoptosis or programmed cell death. Specificagents and additives provided to an organ by the perfusion, diagnosticand/or transporter apparatus, under conditions controlled by theparticular apparatus, may interrupt, decrease and/or reverse apoptosis.

[0146] In preferred methods of the present invention, an organ or tissueis treated ex vivo by mechanical, physical, chemical or geneticmanipulation and/or modification to treat disease and/or treat damage toand/or enhance the properties of the organ or tissue. An organ or tissuesample may be removed from a first body, modified, treated and/oranalyzed outside the first body and returned to the first body ortransplanted to a second body or otherwise used. An advantage of theapparatus is that it enlarges the time that an organ may be availablefor ex vivo treatment, e.g., for hours (e.g. 2, 4, 6, 8, 10, 12 or morehours) or even days (e.g. 2, 4, 6, 8, 10, 12 or more days) or weeks(e.g. 1, 2, 3, 4, 5, 6, 7, 8 or more weeks). In preferred embodiments,the perfusion, diagnostic and/or transporter apparatus of the presentinvention may be used to provide particular solutions or chemicals oragents to an organ or tissue or may be used to perform particulartreatments including flushing or washing an organ or tissue withparticular solutions or chemicals. Ex vivo treatments may be performedon tissue or an organ to be transplanted, may be performed on tissue oran organ that has been removed from a patient and is to be returned tothe patient after the desired procedure is performed, or may beperformed on tissue or an organ that is to be used in substance testingor the like. Ex vivo treatments include but are not limited to treatmentof tissue or an organ that has endured a period or periods of ischemiaand/or apoxia. Ex vivo treatments may involve performing surgicaltechniques on an organ, such as cutting and suturing an organ, forexample to remove necrotic tissue. Any surgical or other treatmenttechnique that may be performed on tissue or an organ in vivo may alsobe performed on tissue or an organ ex vivo. The benefit of such ex vivotreatment may be seen, for example, in the application of radiation orchemotherapy to treat a tumor present in or on an organ, to preventother portions of the patient from being subjected to extraneousradiation or chemotherapy during treatment. The perfusion andtransporter apparatus of the present invention also provide additionaltime for a physician to maintain the tissue or organ before, duringand/or after performing a particular technique on the tissue or organ.

[0147] Particles trapped in an organ's vasculature may prevent the organfrom perfusing properly, or may cause the organ to function improperly,before and/or after transplantation. Perfusion, diagnostic andtransporter apparatus of the invention provide ex vivo techniquesinclude perfusing, flushing or washing an organ with suitable amounts ofa thrombolytic agent, such as streptokinase, to dissolve blood clotsthat have formed or to prevent the formation of blood clots in an organand to open the vasculature of the organ. Such techniques are disclosed,for example, in U.S. patent application Ser. No. 09/938,597, filed Aug.25, 2000, Attorney Docket No. 106996, the entire disclosure of which ishereby incorporated by reference.

[0148] Another concern with organ transplantation is the degree to whicha recipient may be medicated to prevent organ rejection. In organtransplantation, a further ex vivo technique involves modifying theorgan to avoid having it activate the immune system of the donee toprevent or reduce organ rejection and to limit or prevent the need tosuppress the donee's immune system before, during and/or after organtransplantation so as to increase the tolerance of the donee to thetransplanted organ. Modifications of an organ may, for example,encourage the donee body to recognize the transplanted organ asautologous.

[0149] The perfusion, diagnostic and/or transporter apparatus of thepresent invention may deliver substances such as chemical compounds,natural or modified antibodies, immunotoxins or the like, to an organand may assist the organ to adsorb, absorb or metabolize such substancesto increase the likelihood that the organ will not be rejected. Thesesubstances may also mask the organ by blocking, killing, depletingand/or preventing the maturation of allostimulatory cells (dendriticcells, passenger leukocytes, antigen presenting cells, etc.) so that therecipient's immune system does not recognize it or otherwise recognizesthe organ as autologous. An organ may be treated just prior totransplantation or may be pretreated hours, days or weeks beforetransplantation. Such techniques are further described in U.S.Provisional Patent Application No. 60/227,841, filed Aug. 25, 2000,Attorney Docket No. 100034, the entire disclosure of which is herebyincorporated by reference.

[0150] Substances, such as modified or unmodified immunoglobulin,steroids and/or a solution containing polyethylene glycol (PEG) and anantioxidant such as glutathione, may also be provided to an organ ortissue to mask the organ or to treat the onset of intimal hyperplasiaduring cryopreservation and/or organ or tissue transplantation. Thesesolutions may be provided to an organ or tissue by perfusion, diagnosticand/or transporter apparatus of the invention. Exemplary such solutionsand methods are disclosed in U.S. patent application Ser. No.09/499,520, the entire disclosure of which is hereby incorporated byreference.

[0151] As discussed above, the present invention involves avoidingdamage to an organ during perfusion while monitoring, sustaining and/orrestoring the viability of the organ and preserving the organ forstorage and/or transport. However, not all organs that are donated andperfused according to the exemplary embodiments discussed above, areultimately transplanted in a donee. After careful analysis, adetermination might be made that the organ might not be suitable fortransplanting. The organ, however, should not be unnecessarilydiscarded. That is, that same organ determined not to be suitable fortransplantation may serve another purpose.

[0152] According to further exemplary embodiments of this invention, theorgan may be perfused with medical fluids for the purpose of screeningbioactive or other test agents and providing data for research anddevelopment. Since the organ or tissue may be maintained and/or analyzedat or near physiologic parameters, an organ may be tested for theeffects of various treatments using substances such as bioactive agentsor drugs, on the organ or tissue, ex vivo. The ex vivo treatment can beutilized for organs of small mammals, large mammals including livestockanimals such as cattle, pigs, sheep, and goats, and/or humans. Further,the ex vivo treatment of organs may be used for various organs, such asthe kidneys, gut, pancreas, heart and lungs, and may be adapted to morecomplex organs, such as the liver, having multiple vasculaturestructures, for example, the hepatic and portal vasculatures of theliver.

[0153] The perfusion, diagnostic and transporter apparatus of theinvention may be used in conjunction with the above techniques andmethods and/or in conjunction with further techniques and methods, toperform research on an organ or tissue. The various apparatus maypreserve and/or maintain the organ and allow the organ to be availablefor ex vivo use.

[0154] During the period in which the organ is preserved and/ormaintained, various activities may be performed on and/or with theorgan. For example, the organ, or multiple organs simultaneously, may beperfused with a fluid containing a substance, such as one or morebioactive agents or other (e.g. putatively inert agents) to obtain dataregarding the behavior of the substance and/or the organ and/or theinteraction between the substance and the organ.

[0155] The perfusion, diagnostic and/or transporter apparatus may beused to gather data by perfusing blood, a synthetic blood substitute ora combination thereof, or blood cells mixed with a perfusate havingknown or unknown chemical properties, through an organ while monitoringthe organ, organ vascular outflow or other organ outflow, to performresearch and to analyze the condition of the organ and/or to determinethe effect on the organ by screening with the substance. It

[0156] For example, as discussed with respect to FIGS. 28-31 of thepresent invention, the organ diagnostic system 2800 has a computer 2810and an analyzer 2820. Connected to both computer 2810 and analyzer 2820is an organ evaluation instrument 2830 to provide automatic sampling.The systems and method of the invention allow for manual sampling. Theorgan diagnostic system 2800 provides analysis of an organ and theperfusate. According to embodiments of this invention, perfusion of theorgan allows for an organ inflow with a perfusate having a known andpredetermined chemistry. This increases the flexibility of types andcontents of perfusates that may be delivered such as blood or asynthetic blood carrier or a combination thereof, which may be tailoredand/or modified to the particular analysis in process.

[0157] Fluid flow within the system is monitored by flow sensor 3020.The fluid is collected and passed via transfer line 2860 to analyzer2820. The sensed characteristics may be measured by capturing anymeasurable outflow of the organ, such as venous, bile, intraluminal, andurine outflow, and airway measurements from organs such as the lungs andcomparing the sensed characteristics, for example, to characteristics ofthe inflow or of other actual or idealized organs. The venous outflowmay be captured directly and measured or the organ bath may be measuredto provide a rough approximation of the fluid characteristics forcomparisons.

[0158] As discussed above, the organ and medical fluid characteristicsmay optionally be analyzed, for example, in a separate diagnosticapparatus and/or analyzer as shown in FIGS. 28-31. The sensedcharacteristics provide researchers a determination of how much of atest substance went into the organ and how much came out. Further, thetest substance can be labeled with radioisotopes to help track it andits interaction, if any, with the organ. The radioisotopes can betracked with instruments such as a mass spectrometer. The result of suchsensed characteristics may allow the researcher to analyze organscreening results such as absorption, distribution, metabolism,excretion, pharmacokinetics, pharmacodynamics and toxicity may be usedto provide data, for example, for drug development in which the dataultimately may help determine drug efficacy and/or toxicity. The sensedcharacteristics may be analyzed individually or multiple characteristicsmay be analyzed to determine the effect upon and/or interaction betweenthe medical fluid containing a substance and the organ.

[0159] While, as discussed above, the organ diagnostic system 2800analyzes the organ and/or the perfusate and/or the interaction therebetween, data may be generated regarding the outcome of the analysis. Asdiscussed above, FIG. 31 shows a logic circuit for organ diagnosticsystem 2800. The computer provides control parameters and receivesresults and data from the analyzer 2820. The computer further controlsfeatures of the present invention such as auto sampling, control overmaintenance of sampling and other quality assurance features. Datagathered in accordance with embodiments of the invention provide forefficiency in gathering of data regarding for example, absorption,distribution, metabolism and excretion (ADME). The data can be generatedand displayed in real time, stored, transmitted to a remote site, and/ortransferred to a recording medium. Gathering of this type of data allowsfor scientists and researchers to determine what the substance is doingto the organ and conversely, what the organ is doing to the substance.With this data, researchers are able to contribute to a more effectiveand safe research process and analyze substances and their effects, ifany, on organs prior to testing of such substances on a whole animallevel. Additionally, data that may be determined according to thevarious exemplary embodiments discussed above, includes data relating topresystemic elimination, absorption and drug delivery, pharmacokineticsand metabolism, pharmacodynamics, toxicokinetics, drug-druginteractions, and the like. It is within the spirit and scope of thepresent invention that the various exemplary embodiments of thisinvention allow for the gathering of any data relating to thesubstances, the organ, and the interaction therebetween.

[0160] Various data structures and information connections and analysissub records can be facilitated to assist in the overall communicationand data transfers that may be beneficial before, during and aftertreatment of an organ. The perfusion apparatus, transporter, and organdiagnostic apparatus may be networked to permit remote management andmonitoring of the organ, medical fluids and test substances. Theinformation systems may be used to compile data of the organ, themedical fluid, the test substance, and the interaction therebetween. Thesystems may also be used for compiling data regarding chemicalcleanliness and chemical integrity of the systems themselves andproviding information regarding trace amounts of chemical in the system.The systems may also provide outcome data to allow for ready research oforgan and medical fluid and substance, and information may also bedirectly recovered from the perfusion, diagnostic or transporterapparatus to monitor such data. Various types of data and informationmay be grouped into sub-records or sub-directories to assist in datamanagement and transfer. All the sub-records may be combined to form anoverall record, which may be disseminated to or retrievable byphysicians, scientists or other organizations for research purposes.

[0161] Preferred embodiments of the perfusion, diagnostic andtransporter can automatically log much or all of the data into aninternal database. The apparatus may also be connected to a LAN and datauploads can occur intermittently or continuously and in real-time. Datamay be displayed and accessed on the internet to facilitate monitoringfrom any location.

[0162] According to exemplary embodiments, an organ data index isgenerated taking into account the various measured and analyzed factorsidentified above. The data index may be organ specific, or may beadaptable to various organs. The data index compiles the sensedcharacteristics and data into a diagnostic summary to be used for makingorgan treatment and research decisions. The data index may beautomatically generated and provided to the researcher or physician. Theindex is preferably computer generated via a connection to the perfusionapparatus, transporter, and/or organ diagnostic apparatus. Inembodiments, the index may be made available over a computer networksuch as a local area network or the internet for quick comparison,remote analysis and data storage. The organ data index may providemeasurements and normal ranges for each characteristic, such as forabsorption, distribution, metabolism, excretion, pharmacokinetics,pharmacodynamics and toxicity. Measurements that are outside the normalrange may be indicated visually, e.g., by an asterisk or other suitablevisible notation, aurally or by machine perceivable signals. Thecharacteristics give the physician or researcher insight into effectssuch as the metabolism of the organ, such as stability of themetabolism, consumption of glucose, creation of lactic acid and oxygenconsumption.

[0163] The methods according to the invention preferably utilizeapparatus such as that discussed above to perfuse an organ to sustain,monitor and/or restore the viability of an organ and/or to transportand/or store the organ. Organs are often deprived of oxygen (known asischemia) for extended periods of time due to disease or injury to thedonor body, during removal of the organ from the donor body and/orduring storage and/or transport. The perfusion, diagnostic, and/ortransporter apparatus of the present invention have the ability todetect the cell chemistry of an organ in order to adjust the perfusateand control the cellular metabolism to repair ischemic damage to theorgan and to prevent reperfusion injury. One specific outcome ofischemic injury may be apoptosis or programmed cell death. Specificagents and additives provided to an organ by the perfusion, diagnosticand/or transporter apparatus, under conditions controlled by theparticular apparatus, may interrupt, decrease and/or reverse apoptosis.

[0164] Preferred methods according to the present invention focus onthree concepts in order to preserve an organ's viability prior totransplant of the organ into a donee body, or prior to use of the organfor research and development: treating the cellular mitochondria tomaintain and/or restore pre-ischemia energy and enzyme levels,preventing general tissue damage to the organ, and preventing thewashing away of or damage to the vascular endothelial lining of theorgan.

[0165] The mitochondria are the energy source in cells. They need largeamounts of oxygen to function. When deprived of oxygen, their capacityto produce energy is reduced or inhibited. Additionally, at temperaturesbelow 20° C. the mitochondria are unable to utilize oxygen to produceenergy. By perfusing the organ with an oxygen rich medical fluid atnormothermic temperatures, the mitochondria are provided with sufficientamounts of oxygen so that pre-ischemia levels of reserve high energynucleotide, that is, ATP levels, in the organ reduced by the lack ofoxygen are maintained and/or restored along with levels of enzymes thatprotect the organ's cells from free radical scavengers. Pyruvate richsolutions, such as that disclosed in U.S. Pat. No. 5,066,578, areincapable of maintaining and/or restoring an organ's pre-ischemia energylevels and only function in the short term to raise the level of ATP asmall amount. That is, organs naturally have significant pyruvatelevels. Providing an organ with additional pyruvate will not assist inrestoring and/or maintaining the organ's pre-ischemia energy levels ifthe mitochondria are not provided with sufficient oxygen to produceenergy. Thus, the normothermic perfusion fluid may contain pyruvate butmay also contain little or no pyruvate. For example, it can contain lessthan 6 mM of pyruvate, 5 mM, 4 mM, or even no pyruvate. Other knownpreservation solutions, such as that disclosed in U.S. Pat. No.5,599,659, also fail to contain sufficient oxygen to restore and/ormaintain pre-ischemia energy and enzyme levels.

[0166] After maintaining and/or restoring the organ's pre-ischemiaenergy levels by perfusing the organ with an oxygen rich first medicalfluid at normothermic or near-normothermic temperatures (thenormothermic mode), the organ may be perfused with a second medicalfluid at hypothermic temperatures (the hypothermic mode). Thehypothermic temperatures slow the organ's metabolism and conserve energyduring storage and/or transport of the organ. The medical fluid utilizedin the hypothermic mode contains little or no oxygen, which cannot beutilized by mitochondria to produce energy below approximately 20° C.The medical fluid may include antioxidants and other tissue protectingagents, such as, for example, ascorbic acid, glutathione, water solublevitamin E, catalase, or superoxide dismutase to protect against highfree radical formation which occurs at low temperatures due to thereduction in catalase/superoxide dismutase production. Further, variousdrugs and agents such as hormones, vitamins, nutrients, antibiotics andothers may be added to either solution where appropriate. Additionally,vasodilators, such as, for example, peptides, may be added to themedical fluid to maintain flow even in condition of injury.

[0167] Prior to any normothermic perfusion with the oxygen rich firstmedical fluid at normothermic temperatures, the organ may be flushedwith a medical solution containing little or no oxygen and preferablycontaining antioxidants. The flushing is usually performed athypothermic temperatures but can, if desired and/or as necessary, beperformed at normothermic or near-normothermic temperatures. Flushingcan be followed by one or more of hypothermic perfusion, normothermicperfusion, and/or static storage, in any necessary and/or desired order.In some cases, normothermic perfusion or hypothermic perfusion may notbe necessary.

[0168] The normothermic perfusion, with or without prior hypothermicflushing, may also be performed on an organ that has already beensubjected to hypothermic temperatures under static or perfusionconditions, as well as on normothermic organs.

[0169] The organ may be perfused at normothermic or near-normothermictemperatures to sustain, monitor and/or restore its viability priorand/or subsequent to being perfused at hypothermic temperatures forstorage and then may be transported without or preferably withhypothermic perfusion. Also, the normothermic perfusion may be performedin vivo prior to removal of the organ from the donor body. Further, theorgan may be perfused at normothermic temperatures to sustain, monitorand/or restore its viability prior to being perfused at hypothermictemperatures preparatory to storage and/or transport. Then the organ maybe transplanted into a donee body or used for other research whileremaining at hypothermic temperatures, or it may first be subjected tonormothermic perfusion to help it recover from the effects of storageand/or transport. In the latter case, it may then be transplanted orused at normothermic temperatures, or preferably, be hypothermicallyperfused again for transplantation at hypothermic temperatures. Aftertransplant, the organ may optionally again be perfused at normothermictemperatures in vivo, or allowed to warm up from the circulation of thedonee. Substance research is preferably conducted at normothermictemperatures. Further, it is preferable to conduct substance testing inconditions that are close to normal physiological conditions. Forexample, temperature, oxygen levels, and the like.

[0170] By way of example only, and without being limited thereto, FIG.16 shows an exemplary diagram of possible processing steps according tothe invention. The Figure shows various possible processing steps ofmultiple organ recovery (MOR) from organ explant from the organ donorthrough implant in the donee (or other use), including possible WIT(warm ischemia time) and hypoxia damage assessment. Several exemplaryscenarios are set forth in the following discussion.

[0171] For example, in one embodiment of the present invention, theorgan can be harvested from the donor under beating heart conditions.Following harvesting, the organ can be flushed, such as with anysuitable solution or material including, but not limited to VIASPAN (apreservation solution available from DuPont), other crystalloidsolution, dextran, HES (hydroxyethyl starch), solutions described inU.S. patent application Ser. No. 09/628,311, filed Jul. 28, 2000, theentire disclosure of which is hereby incorporated by reference, or thelike. The organ can then be stored statically, for example, at icetemperatures (for example of from about 1 to about 10° C.).

[0172] In another embodiment, such as where the organ has minimal WITand minimal vascular occlusion, a different procedure can be used. Here,the organ can again be harvested under beating heart conditions,followed by flushing, preferably at hypothermic temperatures. Ifnecessary, the organ can be stored in a suitable transporter at, forexample, ice temperatures. Flow to the organ can be controlled by a setpressure maximum, where preset pressure minimum and pressure maximumvalues control the pulse wave configuration. If necessary to store theorgan for a longer period of time, such as for greater than 24 hours,the organ can be placed in the MOR. In the MOR, a suitable perfusate canbe used, such as a crystalloid solution, dextran or the like, andpreferably at hypothermic temperatures. Preferably, the hypothermictemperatures are from about 4 to about 10° C., but higher or lowertemperatures can be used, as desired and/or necessary. Preferably, theperfusate solution contains specific markers to allow for damageassessment, although damage assessment can also be made by other knownprocedures. When desired, the organ can then be returned to thetransporter.

[0173] As a variation of the above procedure, an organ having minimalWIT and minimal vascular occlusion can be harvested under non-beatingheart conditions. Here, the organ can flushed, preferably at hypothermictemperatures and, if necessary, stored for transport in a suitabletransporter at, for example, ice temperatures. As above, flow to theorgan can be controlled by a set pressure maximum, where preset pressureminimum and pressure maximum values control the pulse waveconfiguration. The organ can be placed in the MOR, either for extendedstorage and/or for damage assessment and/or repari. In the MOR, asuitable perfusate can be used, such as a crystalloid solution, dextranor the like, and preferably at hypothermic temperatures. Preferably, thehypothermic temperatures are from about 4 to about 10° C., but higher orlower temperatures can be used, as desired and/or necessary. Preferably,the perfusate solution contains specific markers to allow for damageassessment, although damage assessment can also be made by other knownprocedures. Following hypothermic perfusion, a second perfusion can beutilized, preferably at normothermic temperatures. Any suitableperfusion solution can be used for this process, including solutionsthat contain, as desired, oxygenated media, nutrients, and/or growthfactors. Preferably, the normothermic temperatures are from about 12 toabout 24° C., but higher or lower temperatures, including about 37° C.can be used, as desired and/or necessary. The normothermic perfusion canbe conducted for any suitable period of time, for example, for fromabout 1 hour to about 24 hours. Following recovery from the normothermicperfusion, the organ is preferably returned to a hypothermic perfusionusing, for example, a suitable solution such as a crystalloid solution,dextran or the like, and preferably at hypothermic temperatures. Whendesired, the organ can then be returned to the transporter.

[0174] In embodiments where the organ has high WIT, and/or where thereis a high likelihood of or actual vascular occlusion, variations on theabove processes can be used. For example, in the case where the organ isharvested under non-beating heart conditions, the organ can be flushedas described above. In addition, however, free radical scavengers can beadded to the flush solution, if desired. As above, the organ can bestored for transport in a suitable transporter at, for example, icetemperatures, where flow to the organ can be controlled by a setpressure maximum, and where preset pressure minimum and pressure maximumvalues control the pulse wave configuration. The organ can be placed inthe MOR, either for extended storage and/or for damage assessment and/orrepari. In the MOR, a suitable perfusate can be used, such as acrystalloid solution, dextran or the like, and preferably at hypothermictemperatures. Preferably, the hypothermic temperatures are from about 4to about 10° C., but higher or lower temperatures can be used, asdesired and/or necessary. Preferably, the perfusate solution containsspecific markers to allow for damage assessment, although damageassessment can also be made by other known procedures. Followinghypothermic perfusion, a second perfusion can be utilized, preferably atnormothermic temperatures. Any suitable perfusion solution can be usedfor this process, including solutions that contain, as desired,oxygenated media, nutrients, and/or growth factors. Preferably, thenormothermic temperatures are from about 12 to about 24° C., but higheror lower temperatures can be used, as desired and/or necessary. Thenormothermic perfusion can be conducted for any suitable period of time,for example, for from about 1 hour to about 24 hours. If desired, andparticularly in the event that vascular occlusion is determined orassumed to be present, a further perfusion can be conducted at highernormothermic temperatures, for example of from about 24 to about 37° C.This further perfusion can be conducted using a suitable solution thatcontains a desired material to retard the vascular occlusion. Suchmaterials include, for example, clotbusters such as streptokinase.Following recovery from the normothermic perfusion(s), the organ may bereturned to a hypothermic perfusion using, for example, a suitablesolution such as a crystalloid solution, dextran or the like, andpreferably at hypothermic temperatures. When desired, the organ can thenbe returned to the transporter.

[0175] The organ cassette according to the present invention allows anorgan(s) to be easily transported to an organ recipient and/or betweenorgan perfusion, diagnostic and/or portable transporter apparatus, suchas, for example, transporter 1900 described above or a conventionalcooler or a portable container such as that disclosed in co-pending U.S.application Ser. No. 09/161,919. Because the organ cassette may beprovided with openings to allow the insertion of tubing of an organperfusion, transporter or diagnostic apparatus into the cassette forconnection to an organ disposed therein, or may be provided with its owntubing and connection device or devices to allow connection to tubingfrom an organ perfusion, transporter or diagnostic apparatus and/or alsowith its own valve, it provides a protective environment for an organfor storage, analysis and/or transport while facilitating insertion ofthe organ into and/or connection of an organ to the tubing of an organperfusion, transporter or diagnostic device. Further, the organ cassettemay also include a handle to facilitate transport of the cassette andmay be formed of a transparent material so the organ may be visuallymonitored.

[0176] Optionally, transporter 1900 and/or cassette 65 may include aGlobal Positioning System (GPS) (not shown) to allow tracking of thelocation of the organ(s). The apparatus may also include a data loggerand/or transmitter (not shown) to allow monitoring of the organ(s) atthe location of the apparatus or at another location.

[0177] The method of the invention will be discussed below in terms ofthe operation of the apparatus shown in FIG. 2. However, other apparatusmay be used to perform the inventive method.

[0178] As previously discussed, the apparatus discussed above canoperate in two modes: a normothermic perfusion mode and a hypothermicperfusion mode. The normothermic perfusion mode will be discussed firstfollowed by a discussion of hypothermic perfusion mode. Repetitivedescription will be omitted as much as possible.

[0179] In the normothermic or near-normothermic perfusion mode, an organis perfused for preferably ½ to 6 hours, more preferably ½ to 4 hours,most preferably ½ to 1 hour, with a medical fluid maintained preferablywithin a range of approximately 10° C. to 38° C., more preferably 12° C.to 35° C., most preferably 12° C. to 24° C. or 18° C. to 24° C. (forexample, room temperature 22-23° C.) by the thermoelectric unit 30 adisposed in heat exchange communication with the medical fluid reservoir10.

[0180] As discussed above, in this mode, the medical fluid is preferablyan oxygenated cross-linked hemoglobin-based bicarbonate solution.Cross-linked hemoglobin-based medical fluids can deliver up to 150 timesmore oxygen to an organ per perfusate volume than, for example, a simpleUniversity of Wisconsin (UW) gluconate type perfusate. This allowsnormothermic perfusion for one to two hours to partially or totallyrestore depleted ATP levels. However, the invention is not limited tothis preservation solution. Other preservation solutions, such as thosedisclosed in U.S. Pat. Nos. 5,149,321, 5,234,405 and 5,395,314 andco-pending U.S. patent applications Ser. Nos. 08/484,601 and U.S. patentapplication Ser. No. 09/628,311, filed Jul. 28, 2000, Attorney DocketNo. 101311, the entire disclosures of which are hereby incorporated byreference, may also be appropriate.

[0181] In the normothermic perfusion mode, the medical fluid is feddirectly to an organ disposed within the organ chamber 40 from one orthe other of bags 15 a, 15 b via tubing 50 a, 50 b, 50 c or 50 d, 50 e,50 c, respectively. The organ is perfused at flow rates preferablywithin a range of approximately 3 to 5 ml/gram/min. Pressure sensor P1relays the perfusion pressure to the microprocessor 150, which variesthe pressure supplied by the pressure source 20 to control the perfusionpressure and/or displays the pressure on the control and display areas 5a for manual adjustment. The pressure is preferably controlled within arange of approximately 10 to 100 mm Hg, preferably 50 to 90 mm Hg, bythe combination of the pressure source 20 and pressure cuff 15 a, 15 bin use and the stepping motor/cam valve 65. The compressor and cuffsprovide gross pressure control. The stepping motor/cam valve 65 (orother variable valve or pressure regulator), which is also controlled bythe operator, or by the microprocessor 150 in response to signals fromthe pressure sensor P1, further reduces and fine tunes the pressureand/or puts a pulse wave on the flow into the organ 60. If the perfusionpressure exceeds a predetermined limit, the stepping motor/cam valve 65may be activated to shut off fluid flow to the organ 60.

[0182] The specific pressures, flow rates and length of perfusion timeat the particular temperatures will vary depending on the particularorgan or organs being perfused. For example, hearts and kidneys arepreferably perfused at a pressure of approximately 10 to 100 mm Hg and aflow rate of approximately 3 to 5 ml/gram/min. for up to approximately 2to 4 hours at normothermic temperatures to maintain and/or restore theviability of the organ by restoring and/or maintaining pre-ischemiaenergy levels of the organ, and are then preferably perfused at apressure of approximately 10 to 30 mm Hg and a flow rate ofapproximately 1 to 2 ml/gram/min. for as long as approximately 72 hoursto 7 days at hypothermic temperatures for storage and/or transport.However, these criteria will vary depending on the condition of theparticular organ, the donor body and/or the donee body, the intendeduse, and/or on the size of the particular organ. One of ordinary skillin the art can select appropriate conditions without undueexperimentation in view of the guidance set forth herein.

[0183] Effluent medical fluid collects in the bottom of the organchamber 40 and is maintained within the stated temperature range by thesecond thermoelectric unit 30 b. The temperature sensor T2 relays theorgan temperature to the microprocessor 150, which controls thethermoelectric unit 30 a to adjust the temperature of the medical fluidand organ bath to maintain the organ 60 at the desired temperature,and/or displays the temperature on the control and display areas 5 c formanual adjustment.

[0184] Collected effluent medical fluid is pumped out by the pump 80 viatubing 81 through the filter unit 82 and then returned to the organbath. This filters out surgical and/or cellular debris from the effluentmedical fluid and then returns filtered medical fluid to act as the bathfor the organ 60. Once the level sensor L2 senses that a predeterminedlevel of effluent medical fluid is present in the organ chamber 40(preferably enough to maintain the organ 60 immersed in effluent medicalfluid), additional effluent medical fluid is pumped out by the pump 90through tubing 91. The temperature sensor T1 relays the temperature ofthe organ bath to the microprocessor 150, which controls thethermoelectric unit 30 b to adjust the temperature of the medical fluidto maintain the organ 60 at the desired temperature and/or displays thetemperature on the control and display area 5 c for manual adjustmentand monitoring.

[0185] As noted above, the medical fluid can be directed to waste in asingle pass mode or recirculated eventually back to the organ and/orbath (recirculation mode.)

[0186] Along tubing 91, the recirculated medical fluid is first pumpedthrough the filter unit 95. Use of a cross-linked hemoglobin medicalfluid allows the use of sub-micron filtration to remove large surgicaldebris and cellular debris, as well as bacteria. This allows the use ofminimal antibiotic levels, aiding in preventing organ damage such asrenal damage.

[0187] Next, the recirculated medical fluid is pumped through the CO₂scrubber/O₂ membrane 100. The medical fluid passes over the hydrophobicmacroporous membrane with a hydrophilic coating (for example, Hypol) anda low vacuum is applied on the opposite side by activating valve VV₁which removes CO₂ from the recirculated medical fluid.

[0188] Subsequently, a portion of the medical fluid then enters theoxygenator 110 (for example, a JOSTRA™ oxygenator) and a portion isdiverted therearound passing via tubing 111 though the pH, pO₂, pCO₂,LDH, T/GST and Tprotein sensor V1. At this point two gases, preferably100% oxygen and 95/5% oxygen/carbon dioxide, are respectively placed onthe opposite sides of the membrane depending on the pH level of thediverted medical fluid. The gases are applied at a pressure of up to 200mm Hg, preferably 50 to 100 mm Hg, preferably through a micrometer gasvalve GV₃. The cross-linked hemoglobin-based bicarbonate medical fluidmay be formulated to require a pCO₂ of approximately 40 mm Hg to be atthe mid point (7.35) of a preferred pH range of 7.25-7.45.

[0189] If the medical fluid exiting the oxygenator is within thepreferred pH range (e.g., 7.25-7.45), 100% oxygen is delivered to thegas exchange chamber, and valve LV₁ is then not opened, allowing theperfusate to return to the reservoir 10 into the bag 15 a or 15 b not inuse. If the returning perfusate pH is outside the range on the acidicside (e.g., less than 7.25), 100% oxygen is delivered to the gasexchange chamber and valve LV₁ is then opened allowing the perfusate toreturn to the organ chamber 40. Actuation of syringe pump 131 pumps, forexample, one cc of a bicarbonate solution from the bicarbonate reservoir130, via tubing 132 into the organ bath. Medical fluids with highhemoglobin content provide significant buffering capacity. The additionof bicarbonate aids in buffering capacity and providing a reversible pHcontrol mechanism.

[0190] If the returning perfusate pH is outside the range on the basicside (e.g., greater than 7.25), 95/5% oxygen/carbon dioxide is deliveredto the gas exchange chamber and valve LV₁ is not actuated, allowing theperfusate to return to the bag 15 a or 15 b not in use. The bag 15 a or15 b not in use is allowed to degas (e.g., any excess oxygen) throughvalve GV₄. When the bag 15 a or 15 b in use has approximately 250 ml orless of medical fluid remaining therein, its respective cuff 16 a, 16 bis allowed to vent via its respective gas valve GV₁, GV₂. Then, therespective cuff 16 a, 16 b of the bag 15 a or 15 b previously not in useis supplied with gas from the compressed gas source 20 to delivermedical fluid to the organ to continue perfusion of the organ.

[0191] In the hypothermic mode, an organ is perfused with a cooledmedical fluid, preferably at a temperature within a range ofapproximately 1° C. to 15° C., more preferably 4° C. to 10° C., mostpreferably around 10° C. The medical fluid is preferably a crystalloidperfusate without oxygenation and preferably supplemented withantioxidants and other tissue protecting agents, such as, for example,ascorbic acid, glutathione, water soluble vitamin E, catalase, orsuperoxide dismutase.

[0192] Instead of feeding the medical fluid directly to the organ, themedical fluid may be fed from the reservoir tank 17 via tubing 51 intoan intermediary tank 70 preferably having a pressure head ofapproximately 5 to 40 mm Hg, more preferably 10 to 30 mm Hg, mostpreferably around 20 mm Hg. Medical fluid is then fed by gravity or,preferably, pressure, from the intermediary tank 70 to the organ 60along tubing 50 c by activating a valve LV₆. The level sensor 71 in theintermediary tank 70 is used to control the feed from reservoir tank 17to maintain the desired pressure head. Because the medical fluid is fedto the organ by gravity or, preferably, pressure, in the hypothermicmode, there is less perfusion pressure induced damage to the delicatemicrovasculature of the organ. In fact, the pressure at which the organis perfused is limited by the pressure head to at most 40 mm Hg.

[0193] The stepping motor/cam valve 205 (or other variable valve orpressure regulator) may be arranged on the tubing 50 c to providepulsatile delivery of the medical fluid to the organ 60, to decrease thepressure of the medical fluid fed into the organ 60 for controlpurposes, or to stop flow of medical fluid into the organ 60, asdescribed above.

[0194] Further, in the hypothermic mode, because the organ 60 has lessof a demand for nutrients, the medical fluid may be provided to theorgan 60 intermittently (e.g., every two hours at a flow rate of up toapproximately 100 ml/min.), or at a slow continuous flow rate (e.g., upto approximately 100 ml/min.) over a long period of time. Intermittentperfusion can be implemented in the single pass mode or recirculationmode. The pump 80, filter unit 82 and tube 81 may be used to filter theorgan bath along with use of the pH, pO₂, pCO₂, LDH, T/GST and Tproteinsensor; however, because the organ is unable to utilize oxygen athypothermic temperatures, the oxygenator is not used. If desired and/ornecessary, adequate oxygen can be obtained from filtered room air orother suitable source.

[0195] Both the perfusate flow and the temperature regulation can beautomatically controlled. Such automatic control allows a rapid andreliable response to perfusion conditions during operation. Automaticflow control can be based on the parameters measured from the system,including the perfusate flow rate, the perfusate pH exiting the organ,the organ inlet pressure or timed sequences such as pre-selected flowrates or switching between perfusate modes. Preferably, the flow controlis based on pressure monitoring of the perfusate inflow into the organ.The benefits of automatic flow control include maintaining properoxygenation and pH control while operating under continuous flow orcontrolled intermittent flow. Thermal control of the thermoelectricdevices (TED) can regulate the temperature of the organ cassette orcontainer and the perfusate reservoir. The thermal control is based onthermal measurements made for example by thermistor probes in theperfusate solution or inside the organ or by sensors in the TED.

[0196] The automatic control is preferably effected by an interactivecontrol program using easily operated menu icons and displays. Theparameters may be prestored for selection by a user or programmed by theuser during operation of the system. The control program is preferablyimplemented on a programmed general purpose computer. However, thecontroller can also be implemented on a special purpose computer, aprogrammed microprocessor or microcontroller and peripheral integratedcircuit elements, an ASIC or other integrated circuit, a digital signalprocessor, a hardwired electronic or logic circuit such as a discreteelement circuit, a programmable logic device such as a PLD, PLA, FPGA orPAL, or the like. In general, any device capable of implementing afinite state machine that is in turn capable of implementing the controlprocess described herein may be used. The control program is preferablyimplemented using a ROM. However, it may also be implemented using aPROM, an EPROM, an EEPROM, an optical ROM disk, such as a CD-ROM orDVD-ROM, and disk drive or the like. However, if desired, the controlprogram may be employed using static or dynamic RAM. It may also beimplemented using a floppy disk and disk drive, a writable optical diskand disk drive, a hard drive, flash memory or the like.

[0197] In operation, as seen in FIG. 15, the basic steps of operation tocontrol perfusion of one or more organs include first inputting organdata. The organ data includes at least the type of organ and the mass.Then, the program will prompt the user to select one or more types ofperfusion modes. The types of perfusion modes, discussed above, includehypothermic perfusion, normothermic perfusion, and sequential perfusionusing both normothermic and hypothermic perfusion. When bothnormothermic and hypothermic perfusion are employed, the user can selectbetween medical fluids at different temperatures. Of course, the systemincludes default values based on previously stored values appropriatefor the particular organ. The user may also select intermittentperfusion, single pass perfusion, and recirculation perfusion. Dependingon the type of perfusion selected, aerobic or anaerobic medical fluidsmay be specified.

[0198] Next, the type of flow control for each selected perfusion modeis set. The flow control selector selects flow control based on at leastone of perfusate flow rate, perfusate pH, organ inlet pressure and timedsequences. In the preferred embodiment, the flow control is based ondetected pressure at the perfusion inlet to the organ. The flow of themedical fluid is then based on the selected perfusion mode and flowcontrol.

[0199] During operation the conditions experienced by the system, inparticular by the organ and the perfusate, are detected and monitored.The detected operating conditions are compared with prestored operatingconditions. A signal can then be generated indicative of organ viabilitybased on the comparison. The various detectors, sensors and monitoringdevices are described above, but include at least a pressure sensor, apH detector, an oxygen sensor and a flow meter.

[0200] The control system may also include a thermal controller forcontrolling temperature of at least one of the perfusate and the organ.The thermal controller can control the temperature of the medical fluidreservoirs and the organ container by controlling the TEDs. As notedabove, temperature sensors are connected to the controller to facilitatemonitoring and control.

[0201] The control system may be manually adjusted at any time or set tofollow default settings. The system includes a logic circuit to preventthe operator from setting parameters that would compromise the organ'sviability. As noted above, the system may also be operated in a manualmode for sequential hypothermic and/or normothermic perfusion, as wellas in the computer controlled mode for sequential hypothermic and/ornormothermic perfusion.

[0202] The above described apparatus and method may be used for child orsmall organs as well as for large or adult organs with modification asneeded of the cassettes and or of the pressures and flow ratesaccordingly. As previously discussed, the organ cassette(s) can beconfigured to the shapes and sizes of specific organs or organ sizes.The apparatus and method can also be used to provide an artificial bloodsupply to, such, for example, artificial placentas cell cultures, forgrowing/cloning organ(s).

[0203] While the invention has been described in conjunction withspecific embodiments thereof, it is evident that many alternatives,modifications and variations may be apparent to those skilled in theart. Accordingly, the preferred embodiments of the invention as setforth herein are intended to be illustrative, not limiting. Variouschanges may be made without departing from the spirit and scope of theinvention.

What is claimed is:
 1. A method of determining effects of a substance onan organ, comprising: perfusing the at least one organ with a firstmedical fluid to preserve the at least one organ; exposing the at leastone organ to at least one test substance; and gathering data regardingat least one of the at least one organ, the at least one test substance,and interaction between the at least one organ and the at least one testsubstance.
 2. The method of claim 1, wherein the exposing step iscarried out by perfusing the organ with a second medical fluidcontaining the test substance.
 3. The method of claim 2, wherein thefirst and second medical fluids are the same.
 4. The method of claim 2,wherein the first and second medical fluids are different.
 5. The methodof claim 1, wherein at least one of the at least one organ and aneffluent from the organ is monitored by a sensor that sensescharacteristics of at least one of the effluent and the at least oneorgan.
 6. The method of claim 5, further comprising generating datacomprised of the sensed characteristics.
 7. The method of claim 6,wherein the data can be generated and displayed in real time, stored,transmitted to a remote site, transferred to a recording medium, orrelayed to a microprocessor for assessment.
 8. The method of claim 2,further comprising collecting the second medical fluid that has passedthrough the at least one organ from an organ bath and sensingcharacteristics of the collected medical fluid indicative of theinteraction between the at least one organ and the test substance. 9.The method of claim 2, wherein the test substance is a chemicalcompound.
 10. The method of claim 2, wherein the test substance is atleast one of natural and modified antibodies.
 11. The method of claim 2,wherein the test substance is an immunotoxin.
 12. The method of claim 2,wherein the second medical fluid is blood.
 13. The method of claim 5,wherein the sensed characteristics relate to at least one of absorption,distribution, metabolism and excretion.
 14. The method of claim 5,wherein the sensed characteristics relate to at least one ofpharmacokinetics, pharmacodynamics and toxicity.
 15. The method of claim5, wherein the sensed characteristics relate to at least one ofdetermining what the substance is doing to the at least one organ andwhat the at least one organ is doing to the substance.
 16. A method ofscreening at least one organ with a bioactive agent, comprising:determining that the at least one organ will not be transplanted;perfusing said at least one organ with a first medical fluid to preservethe organ; exposing the at least one organ to at least one testsubstance; and gathering data regarding at least one of the at least oneorgan, the at least one test substance, and interaction between the atleast one organ and the at least one test substance.
 17. The method ofclaim 16, wherein the organ is not suitable for transplanting.
 18. Themethod of claim 16, further comprising the steps of: perfusing the atleast one organ with a first medical fluid; and sensing fluidcharacteristics indicative of organ viability.